# System Variable Differences Between MariaDB 10.3 and MySQL 8.0

The following is a comparison of variables that either appear only in [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103) or MySQL 8.0, or have different default settings in [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103), and MySQL 8.0. [MariaDB 10.3.10](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/10.3.10) and MySQL 8.0.11, with only default plugins enabled, were used for the comparison. Note that MySQL 8 is an 'evergreen' release, so features may be added or removed in later releases.

The most notable differences are that MariaDB includes, by default, the [Aria](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria) storage engine (resulting in extra memory allocation), [Galera Cluster](https://github.com/mariadb-corporation/docs-release-notes/blob/test/kb/en/galera/README.md), and has a different [thread pool implementation](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb). For this reason, a default implementation of [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103) will use more memory than MySQL 8.0. [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103) and MySQL 8.0 also have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).

MariaDB's extra memory usage can be handled with the following rules of thumb:

* If you are not using [MyISAM](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine) and don't plan to use [Aria](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria):
  * Set [key\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#key_buffer_size) to something very low (16K) as it's not used.
  * Set [aria\_pagecache\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#aria_pagecache_buffer_size) to what you think you need for handling internal tmp tables that didn't fit in memory.
  * Normally this is what before you had set for [key\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#key_buffer_size) (at least 1M).
* If you are using [MyISAM](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine) and not planning to use [Aria](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria):
  * Set [aria\_pagecache\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#aria_pagecache_buffer_size) to what you think you need for handling internal tmp tables that didn't fit in memory.
* If you are planning to use [Aria](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria), you should set [aria\_pagecache\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#aria_pagecache_buffer_size) to something that fits a big part of your normal data + overflow temporary tables.

## Comparison Table

| Variable                                                                                                                                                                                                                                            | [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103) Default                        | MySQL 8.0 Default                                                                                                                          | Notes                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| activate\_all\_roles\_on\_login                                                                                                                                                                                                                     | -                                                                                                                                            | OFF                                                                                                                                        | Determines whether to automatically activate [roles](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/user-account-management/roles) on login.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [alter\_algorithm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#alter_algorithm)                                                                                                    | DEFAULT                                                                                                                                      | -                                                                                                                                          | [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103) introduces new [ALTER TABLE ALGORITHM](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/data-definition/alter/alter-table#algorithm) clauses to avoid slow copies in certain instances. This variable allows setting this if no ALGORITHM clause is specified.                                                                                                                                                                                                                                                                                                         |
| [aria\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables)                                                                                                                                  | \*                                                                                                                                           | -                                                                                                                                          | The Aria storage engine is only available in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| auto\_generate\_certs                                                                                                                                                                                                                               | -                                                                                                                                            | ON                                                                                                                                         | Whether to automatically generate SSL key and certificate files.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| avoid\_temporal\_upgrade                                                                                                                                                                                                                            | -                                                                                                                                            | OFF                                                                                                                                        | Determines whether ALTER TABLE implicitly upgrades temporal columns.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [back\_log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#back_log)                                                                                                                  | Autosized                                                                                                                                    | Autosized                                                                                                                                  | MariaDB and MySQL have different autosizing algorithms.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| [binlog-annotate-row-events](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/clients-and-utilities/logging-tools/mariadb-binlog/annotate_rows_log_event#master-option-binlog-annotate-row-events)                                                    | ON                                                                                                                                           | -                                                                                                                                          | Introduced in [MariaDB 5.3](https://mariadb.com/docs/release-notes/community-server/old-releases/5.3/changes-improvements-in-mariadb-5-3) for [replicating](https://github.com/mariadb-corporation/docs-server/blob/test/release-notes/compatibility-and-differences/system-variable-differences-between-mariadb-and-mysql/system-variable-differences-between-mariadb-and-mysql-unmaintained-series/broken-reference/README.md) between [MariaDB 5.3](https://mariadb.com/docs/release-notes/community-server/old-releases/5.3/changes-improvements-in-mariadb-5-3) and MySQL/[MariaDB 5.1](https://mariadb.com/docs/release-notes/community-server/old-releases/5.1/changes-improvements-in-mariadb-5-1). |
| [binlog\_commit\_wait\_count](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                   | 0                                                                                                                                            | -                                                                                                                                          | For use in MariaDB's [parallel replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [binlog\_commit\_wait\_usec](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                    | 100000                                                                                                                                       | -                                                                                                                                          | For use in MariaDB's [parallel replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| binlog\_error\_action                                                                                                                                                                                                                               |                                                                                                                                              | ABORT\_SERVER                                                                                                                              | MySQL-only variable for controlling what happens when the server cannot write to the binary log.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| binlog\_expire\_logs\_seconds                                                                                                                                                                                                                       | -                                                                                                                                            | 2592000                                                                                                                                    | Sets the binary log expiration period in seconds                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [binlog\_file\_cache\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                     | 16184                                                                                                                                        | -                                                                                                                                          | For setting the size of the file cache for the [binary log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [binlog\_format](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                                | MIXED                                                                                                                                        | ROW                                                                                                                                        | MariaDB and MySQL have differing [binary log formats](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log/binary-log-formats).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| binlog\_group\_commit\_sync\_delay                                                                                                                                                                                                                  |                                                                                                                                              | 0                                                                                                                                          | MySQL-only variable for controlling the wait time before synchronizing the binary log file to disk.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| binlog\_group\_commit\_sync\_no\_delay\_count                                                                                                                                                                                                       |                                                                                                                                              | 0                                                                                                                                          | MySQL-only variable for setting the maximum number of transactions to wait for before aborting the current binlog\_group\_commit\_sync\_delay delay.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| binlog\_gtid\_simple\_recovery                                                                                                                                                                                                                      | -                                                                                                                                            | ON                                                                                                                                         | MySQL-only GTID variable. MariaDB's [GTID](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid) implementation is different.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| binlog\_max\_flush\_queue\_time                                                                                                                                                                                                                     | -                                                                                                                                            | 0                                                                                                                                          | Specifies a timeout for reading transactions from the flush queue before continuing with group commit and syncing log to disk.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [binlog\_optimize\_thread\_scheduling](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                          | ON                                                                                                                                           | -                                                                                                                                          | For optimized kernel thread scheduling.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| binlog\_order\_commits                                                                                                                                                                                                                              | -                                                                                                                                            | ON                                                                                                                                         | Determines whether transactions may be committed in parallel.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| binlog\_row\_metadata                                                                                                                                                                                                                               | -                                                                                                                                            | MINIMAL                                                                                                                                    | Determines the amount of table metadata added to the binary log with row-based logging.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| binlog\_row\_value\_options                                                                                                                                                                                                                         | -                                                                                                                                            | (empty)                                                                                                                                    | Permits an alternative binlog format for JSON document updates.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| binlog\_rows\_query\_log\_events                                                                                                                                                                                                                    | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variable for logging extra information in row-based logging.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| binlog\_transaction\_dependency\_history\_size                                                                                                                                                                                                      | -                                                                                                                                            | 25000                                                                                                                                      | Maximum number of row hashes kept for looking up transactions that last modified a given row.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| binlog\_transaction\_dependency\_tracking                                                                                                                                                                                                           | -                                                                                                                                            | COMMIT\_ORDER                                                                                                                              | For determining how to best use the slave's multithreaded applier.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| block\_encryption\_mode                                                                                                                                                                                                                             | -                                                                                                                                            | aes-128-ecb                                                                                                                                | MySQL-only variable for controlling the block encryption mode for block-based algorithms.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| caching\_sha2\_password\*                                                                                                                                                                                                                           | -                                                                                                                                            | \*                                                                                                                                         | For use with MySQL's SHA-256 authentication with caching.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [character\_set\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#character_set_client)                                                                                             | latin1 or utf8                                                                                                                               | utf8mb4                                                                                                                                    | MySQL 8.0 defaults to the utf8mb4 [character set](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/string-data-types/character-sets).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [check\_constraint\_checks](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#check_constraint_checks)                                                                                   | ON                                                                                                                                           | -                                                                                                                                          | Permits disabling constraint checks, for example when loading a table that violates some constraints that you plan to fix later.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| check\_proxy\_users                                                                                                                                                                                                                                 |                                                                                                                                              | OFF                                                                                                                                        | MySQL-only variable for controlling whether the server performs proxy user mapping for authentication plugins.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [collation\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#collation_connection)                                                                                                  | latin1\_swedish\_ci or utf8\_general\_ci                                                                                                     | utf8mb4\_0900\_ai\_ci                                                                                                                      | MySQL 8.0 defaults to the utf8mb4 [character set](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/string-data-types/character-sets).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [column\_compression\_threshold](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression#column_compression_threshold)          | 100                                                                                                                                          | -                                                                                                                                          | MariaDB supports [Storage-engine Independent Column Compression](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression).                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [column\_compression\_zlib\_level](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression#column_compression_zlib_level)       | 6                                                                                                                                            | -                                                                                                                                          | MariaDB supports [Storage-engine Independent Column Compression](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression).                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [column\_compression\_zlib\_strategy](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression#column_compression_zlib_strategy) | DEFAULT\_STRATEGY                                                                                                                            | -                                                                                                                                          | MariaDB supports [Storage-engine Independent Column Compression](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression).                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [column\_compression\_zlib\_wrap](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression#column_compression_zlib_wrap)         | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB supports [Storage-engine Independent Column Compression](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimization-and-tuning-compression/storage-engine-independent-column-compression).                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| cte\_max\_recursion\_depth                                                                                                                                                                                                                          | -                                                                                                                                            | 1000                                                                                                                                       | When MySQL 8.0 introduced [common table expressions](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/data-manipulation/selecting-data/common-table-expressions) they used a different name. MariaDB's variable is called [max\_recursive\_iterations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_recursive_iterations).                                                                                                                                                                                                                                                                                       |
| [date\_format](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#date_format)                                                                                                            | %Y-%m-%d                                                                                                                                     | -                                                                                                                                          | Unused variable removed in MySQL 8.0                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [datetime\_format](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#datetime_format)                                                                                                    | %Y-%m-%d                                                                                                                                     | -                                                                                                                                          | Unused variable removed in MySQL 8.0                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [deadlock\_search\_depth\_long](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#deadlock_search_depth_long)                                                                                  | 15                                                                                                                                           | -                                                                                                                                          | The Aria storage engine is only available in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [deadlock\_search\_depth\_short](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#deadlock_search_depth_short)                                                                                | 4                                                                                                                                            | -                                                                                                                                          | The Aria storage engine is only available in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [deadlock\_timeout\_long](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#deadlock_timeout_long)                                                                                             | 50000000                                                                                                                                     | -                                                                                                                                          | The Aria storage engine is only available in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [deadlock\_timeout\_short](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#deadlock_timeout_short)                                                                                           | 10000                                                                                                                                        | -                                                                                                                                          | The Aria storage engine is only available in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [debug\_no\_thread\_alarm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#debug_no_thread_alarm)                                                                                      | OFF                                                                                                                                          | -                                                                                                                                          | Disable system thread alarm calls, for debugging or testing.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| default\_authentication\_plugin                                                                                                                                                                                                                     | -                                                                                                                                            | caching\_sha2\_password                                                                                                                    | MySQL 8 introduced a new authentication plugin.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| default\_collation\_for\_utf8mb4                                                                                                                                                                                                                    | -                                                                                                                                            | utf8mb4\_0900\_ai\_ci                                                                                                                      | For internal use in MySQL 8 replication.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [default\_master\_connection](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                   | empty                                                                                                                                        | -                                                                                                                                          | For use with MariaDB's [multi-source replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/multi-source-replication).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| default\_password\_lifetime                                                                                                                                                                                                                         |                                                                                                                                              | 0                                                                                                                                          | MySQL-only variable determining how long passwords are valid for before expiring.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [default\_regex\_flags](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#default_regex_flags)                                                                                           | empty                                                                                                                                        | -                                                                                                                                          | For handling incompatibilities between MariaDB's [PCRE](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-functions/string-functions/regular-expressions-functions/pcre) and the old regex library.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [default\_tmp\_storage\_engine](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#default_tmp_storage_engine)                                                                            | empty                                                                                                                                        | InnoDB                                                                                                                                     | Default storage engine used for tables created with [CREATE TEMPORARY TABLE](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/tables/create-table).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| disabled\_storage\_engines                                                                                                                                                                                                                          |                                                                                                                                              | empty                                                                                                                                      | MySQL-only variable for disabling specific storage engines.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| disconnect\_on\_expired\_password                                                                                                                                                                                                                   | -                                                                                                                                            | ON                                                                                                                                         | MySQL permits passwords to be expired.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| [encrypt\_binlog](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables#encrypt_binlog)                                                                                | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB enables [table and tablespace encryption](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-at-rest-encryption/data-at-rest-encryption-overview).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [encrypt\_tmp\_files](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#encrypt_tmp_files)                                                                                               | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB enables [table and tablespace encryption](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-at-rest-encryption/data-at-rest-encryption-overview).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [encrypt\_tmp\_disk\_tables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#encrypt_tmp_disk_tables)                                                                                  | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB enables [table and tablespace encryption](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-at-rest-encryption/data-at-rest-encryption-overview).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| end\_markers\_in\_json                                                                                                                                                                                                                              | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variable for adding end markers to JSON output.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| enforce\_gtid\_consistency                                                                                                                                                                                                                          | -                                                                                                                                            | OFF                                                                                                                                        | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [enforce\_storage\_engine](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#enforce_storage_engine)                                                                                     | none                                                                                                                                         |                                                                                                                                            | Forces the use of a particular storage engine for new tables.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [eq\_range\_index\_dive\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#eq_range_index_dive_limit)                                                                             | 0                                                                                                                                            | 200                                                                                                                                        | Variable for tuning when the optimizer should switch from using index dives to index statistics for qualifying rows estimation.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [event\_scheduler](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#event_scheduler)                                                                                                    | OFF                                                                                                                                          | ON                                                                                                                                         | MySQL enables the event scheduler by default.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [expensive\_subquery\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#expensive_subquery_limit)                                                                                 | 100                                                                                                                                          | -                                                                                                                                          | Used for determining expensive queries for optimization.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [explicit\_defaults\_for\_timestamp](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#explicit_defaults_for_timestamp)                                                                  | OFF                                                                                                                                          | ON                                                                                                                                         | MySQL 8 disables the old timestamp behavior.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [extra\_max\_connections](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                     | 1                                                                                                                                            | -                                                                                                                                          | Introduced in the [MariaDB 5.1 threadpool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb-51-53).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| [extra\_port](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                                 | 0                                                                                                                                            | -                                                                                                                                          | Introduced in the [MariaDB 5.1 threadpool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb-51-53).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| [group\_concat\_max\_len](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#group_concat_max_len)                                                                                        | 1048576                                                                                                                                      | 1024                                                                                                                                       | MariaDB increases the maximum length for a [GROUP\_CONCAT()](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-functions/aggregate-functions/group_concat) result from 1K to 1M.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [gtid\_binlog\_pos](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                    | empty                                                                                                                                        | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_binlog\_state](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                  | empty                                                                                                                                        | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_current\_pos](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                   | empty                                                                                                                                        | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_domain\_id](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                     | 0                                                                                                                                            | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| gtid\_executed                                                                                                                                                                                                                                      | -                                                                                                                                            | empty                                                                                                                                      | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| gtid\_executed\_compression\_period                                                                                                                                                                                                                 | -                                                                                                                                            | 1000                                                                                                                                       | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_ignore\_duplicates](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                             | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| gtid\_mode                                                                                                                                                                                                                                          | -                                                                                                                                            | OFF                                                                                                                                        | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| gtid\_next                                                                                                                                                                                                                                          | -                                                                                                                                            | AUTOMATIC                                                                                                                                  | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| gtid\_owned                                                                                                                                                                                                                                         | -                                                                                                                                            | empty                                                                                                                                      | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_pos\_auto\_engines](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid#gtid_pos_auto_engines)                                                                                                       | empty                                                                                                                                        | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| gtid\_purged                                                                                                                                                                                                                                        | -                                                                                                                                            | empty                                                                                                                                      | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_seq\_no](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                        | 0                                                                                                                                            | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_slave\_pos](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                     | empty                                                                                                                                        | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [gtid\_strict\_mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid)                                                                                                                                   | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [have\_crypt](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#have_crypt)                                                                                                              | YES                                                                                                                                          | -                                                                                                                                          | MySQL has removed the [ENCRYPT](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-functions/secondary-functions/encryption-hashing-and-compression-functions/encrypt) function.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| [have\_openssl](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-in-transit-encryption/ssltls-system-variables)                                                                                                              |                                                                                                                                              |                                                                                                                                            | MariaDB's version indicates whether YaSSL or openssl was used. MySQL's is a synonym for have\_ssl.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [have\_query\_cache](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#have_query_cache)                                                                                                 | YES                                                                                                                                          | -                                                                                                                                          | MySQL has removed the [query cache](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/query-cache).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| have\_statement\_timeout                                                                                                                                                                                                                            | -                                                                                                                                            |                                                                                                                                            | Whether MySQL's statement execution timeout feature is available.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [have\_symlink](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#have_symlink)                                                                                                          | YES                                                                                                                                          | DISABLED                                                                                                                                   | MySQL has removed symlink support.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| histogram\_generation\_max\_mem\_size                                                                                                                                                                                                               | -                                                                                                                                            | 20000000                                                                                                                                   | Added when MySQL 8 introduced [Histogram-based Statistics](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/statistics-for-optimizing-queries/histogram-based-statistics). MariaDB uses [histogram\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#histogram_size)                                                                                                                                                                                                                                                                                                         |
| [histogram\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#histogram_size)                                                                                                      | 0                                                                                                                                            | -                                                                                                                                          | MariaDB introduced [Histogram-based Statistics](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/statistics-for-optimizing-queries/histogram-based-statistics).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [histogram\_type](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#histogram_type)                                                                                                      | SINGLE\_PREC\_HB                                                                                                                             | -                                                                                                                                          | MariaDB introduced [Histogram-based Statistics](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/statistics-for-optimizing-queries/histogram-based-statistics).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [idle\_readonly\_transaction\_timeout](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#idle_readonly_transaction_timeout)                                                              | 0                                                                                                                                            | -                                                                                                                                          | Time in seconds that the server waits for idle read-only transactions.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| [idle\_transaction\_timeout](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#idle_transaction_timeout)                                                                                 | 0                                                                                                                                            | -                                                                                                                                          | Time in seconds that the server waits for idle transactions.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [idle\_write\_transaction\_timeout](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#idle_write_transaction_timeout)                                                                    | 0                                                                                                                                            | -                                                                                                                                          | Time in seconds that the server waits for idle write transactions.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [ignore\_builtin\_innodb](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                               | OFF                                                                                                                                          | -                                                                                                                                          | Ignored and removed in MySQL 8.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [in\_transaction](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#in_transaction)                                                                                                      | 0                                                                                                                                            | -                                                                                                                                          | Set to 1 if you are in a transaction, and 0 if not.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| information\_schema\_stats\_expiry                                                                                                                                                                                                                  | -                                                                                                                                            | 86400                                                                                                                                      | Time until MySQL Information Schema cached statistics expire.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [innodb\_adaptive\_flushing\_lwm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                       | 10.000000                                                                                                                                    | 10                                                                                                                                         | Adaptive flushing is enabled when this low water mark percentage of the redo log capacity is reached. MariaDB's variable is a [double](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/numeric-data-types/double), MySQL's an [integer](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/numeric-data-types/int).                                                                                                                                                                                                                                                                                                                                                    |
| innodb\_api\_\*                                                                                                                                                                                                                                     | -                                                                                                                                            | \*                                                                                                                                         | Specific to MySQL's memcached, removed in [MariaDB 10.2](https://mariadb.com/docs/release-notes/community-server/old-releases/10.2/what-is-mariadb-102).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [innodb\_autoinc\_lock\_mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                           | 1                                                                                                                                            | 2                                                                                                                                          | MariaDB has an extra mode, 3, for skipping the rollback of connected transactions. MySQL defaults to row-based replication, so can safely use 2.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [innodb\_background\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                | \*                                                                                                                                           | -                                                                                                                                          | MariaDB has support for [data scrubbing](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-data-scrubbing).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [innodb\_checksums](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                     | ON                                                                                                                                           | -                                                                                                                                          | Deprecated option removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [innodb\_compression\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                               | \*                                                                                                                                           | -                                                                                                                                          | Introduced with MariaDB's [InnoDB compression](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-page-compression).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| innodb\_dedicated\_server                                                                                                                                                                                                                           | -                                                                                                                                            | OFF                                                                                                                                        | MySQL option that automatically configures various settings if the server is a dedicated InnoDB database server.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [innodb\_default\_encryption\_key\_id](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                  | 1                                                                                                                                            | -                                                                                                                                          | Default encryption key id used for table encryption. See [Data at Rest Encryption](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-at-rest-encryption/data-at-rest-encryption-overview).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [innodb\_defragment](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                    | \*                                                                                                                                           | -                                                                                                                                          | MariaDB can [defragment InnoDB tablespaces](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/optimizing-tables/defragmenting-innodb-tablespaces).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| innodb\_directories                                                                                                                                                                                                                                 | -                                                                                                                                            | (empty)                                                                                                                                    | Used to search for tablespace files when moving or restoring a new location.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [innodb\_disallow\_writes](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                              | OFF                                                                                                                                          | -                                                                                                                                          | Tell InnoDB to stop any writes to disk.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| [innodb\_encrypt\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                   | 1                                                                                                                                            | -                                                                                                                                          | See MariaDB's [Data at Rest Encryption](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-at-rest-encryption/data-at-rest-encryption-overview).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [innodb\_fatal\_semaphore\_wait\_threshold](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                             | 600                                                                                                                                          | -                                                                                                                                          | MariaDB's fatal semaphore timeout is configurable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [innodb\_flush\_neighbors](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                              | 1                                                                                                                                            | 0                                                                                                                                          | MySQL 8 by default now assumes the use of an SSD device.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [innodb\_force\_primary\_key](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                           | OFF                                                                                                                                          | -                                                                                                                                          | If set to 1 in MariaDB (0 is default) CREATE TABLEs without a primary or unique key where all keyparts are NOT NULL will not be accepted, and will return an error.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [innodb\_idle\_flush\_pct](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                              | 100                                                                                                                                          | -                                                                                                                                          | Up to what percentage of dirty pages in MariaDB should be flushed when InnoDB finds it has spare resources to do so.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [innodb\_immediate\_scrub\_data\_uncompressed](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                          | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB has support for [data scrubbing](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-data-scrubbing).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [innodb\_lock\_schedule\_algorithm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                     | VATS                                                                                                                                         | -                                                                                                                                          | MariaDB has an improved algorithm for deciding which of the waiting transactions should be granted a lock once it has been released.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [innodb\_locks\_unsafe\_for\_binlog](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                    | OFF                                                                                                                                          | -                                                                                                                                          | Deprecated option in MariaDB for disabling gap locking for searches and index scans. Deprecated in MariaDB, use [READ COMMITTED transaction isolation](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/administrative-sql-statements/set-commands/set-transaction#read-committed) instead.                                                                                                                                                                                                                                                                                                                                                                                          |
| [innodb\_log\_optimize\_ddl](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                            | ON                                                                                                                                           | -                                                                                                                                          | Whether redo logging should be reduced when natively creating indexes or rebuilding tables                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| innodb\_log\_spin\_\*                                                                                                                                                                                                                               | -                                                                                                                                            | \*                                                                                                                                         | MySQL variables for constraining CPU usage while waiting for flushed redo.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| innodb\_log\_wait\_for\_flush\_spin\_hwm                                                                                                                                                                                                            | -                                                                                                                                            | \*                                                                                                                                         | MySQL variable for constraining CPU usage while waiting for flushed redo.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [innodb\_max\_dirty\_pages\_pct](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                        | 75                                                                                                                                           | 90                                                                                                                                         | MySQL 8 increased the default to 90.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [innodb\_max\_dirty\_pages\_pct\_lwm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                   | 0                                                                                                                                            | 10                                                                                                                                         | MySQL 8 increased the default to 10.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [innodb\_max\_undo\_log\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                          | 10485760                                                                                                                                     | 1073741824                                                                                                                                 | [MariaDB 10.2](https://mariadb.com/docs/release-notes/community-server/old-releases/10.2/what-is-mariadb-102) reduced the limit for when an undo tablespace is marked for truncation.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [innodb\_open\_files](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                   | Autosized (2000)                                                                                                                             | Autosized (4000)                                                                                                                           | In most systems, autosized based on the [table\_open\_cache](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#table_open_cache) setting, which differs between MariaDB and MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [innodb\_prefix\_index\_cluster\_optimization](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                          | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB includes the Facebook prefix index queries optimization.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| innodb\_print\_ddl\_logs                                                                                                                                                                                                                            | -                                                                                                                                            | OFF                                                                                                                                        | MySQL option for writing DDL logs to stderr.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| innodb\_redo\_log\_encrypt                                                                                                                                                                                                                          | -                                                                                                                                            | OFF                                                                                                                                        | MySQL 8 has also now introduced redo log encryption, but used a different name. The equivalent option in MariaDB is [innodb\_encrypt\_log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables).                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| [innodb\_scrub\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                     | \*                                                                                                                                           | -                                                                                                                                          | MariaDB includes options to [scrub the redo log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-data-scrubbing).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [innodb\_spin\_wait\_delay](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                             | 4                                                                                                                                            | 6                                                                                                                                          | MariaDB changed the default from 6 to 4 based on extensive benchmarking.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [innodb\_stats\_modified\_counter](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                      | 0                                                                                                                                            | -                                                                                                                                          | MariaDB option to control the calculation of new statistics.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [innodb\_stats\_sample\_pages](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                          | 8                                                                                                                                            | -                                                                                                                                          | Deprecated MariaDB option for control over index distribution statistics.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [innodb\_stats\_traditional](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                            | ON                                                                                                                                           | -                                                                                                                                          | Enabling gives a larger sample of pages for larger tables for the purposes of index statistics calculation.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| innodb\_undo\_log\_encrypt                                                                                                                                                                                                                          | -                                                                                                                                            | OFF                                                                                                                                        | MySQL option for encrypting undo logs residing in separate undo tablespaces.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [innodb\_undo\_log\_truncate](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                           | OFF                                                                                                                                          | ON                                                                                                                                         | MySQL 8 changes the default to ON, marking larger undo logs for truncation.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [innodb\_undo\_logs](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                                    | 128                                                                                                                                          | -                                                                                                                                          | Removed in MySQL 8.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [innodb\_undo\_tablespaces](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                             | 0                                                                                                                                            | 2                                                                                                                                          | Number of tablespace files used for dividing up the undo logs. MySQL 8 has deprecated this setting, and increased the default (and minimum) to 2.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [innodb\_use\_atomic\_writes](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/innodb/innodb-system-variables)                                                                                                           | ON                                                                                                                                           | -                                                                                                                                          | [Atomic writes](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/install-and-upgrade-mariadb/configuring-mariadb/mariadb-performance-advanced-configurations/atomic-write-support) are a faster alternative to innodb\_doublewrite and MariaDB automatically detects when supporting SSD cards are used.                                                                                                                                                                                                                                                                                                                                                                                    |
| internal\_tmp\_disk\_storage\_engine                                                                                                                                                                                                                | -                                                                                                                                            | INNODB                                                                                                                                     | MySQL uses this variable to set the storage engine for on-disk internal temporary tables.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| internal\_tmp\_mem\_storage\_engine                                                                                                                                                                                                                 | -                                                                                                                                            | TEMPTABLE                                                                                                                                  | MySQL and MariaDB use different formats for temporary tables. In MariaDB, the [aria\_used\_for\_temp\_tables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/aria/aria-system-variables#aria_used_for_temp_tables) performs a similar function.                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [join\_buffer\_space\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#join_buffer_space_limit)                                                                                  | 2097152                                                                                                                                      | -                                                                                                                                          | Maximum size in bytes of the query buffer. See [block-based join algorithms](https://mariadb.com/docs/release-notes/community-server/about/compatibility-and-differences/system-variable-differences-between-mariadb-and-mysql/system-variable-differences-between-mariadb-and-mysql-unmaintained-series/broken-reference).                                                                                                                                                                                                                                                                                                                                                                                 |
| [join\_cache\_level](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#join_cache_level)                                                                                                 | 2                                                                                                                                            | -                                                                                                                                          | For determining the join algorithms. See [block-based join algorithms](https://mariadb.com/docs/release-notes/community-server/about/compatibility-and-differences/system-variable-differences-between-mariadb-and-mysql/system-variable-differences-between-mariadb-and-mysql-unmaintained-series/broken-reference).                                                                                                                                                                                                                                                                                                                                                                                       |
| [key\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#key_buffer_size)                                                                                      | 134217728                                                                                                                                    | 8388608                                                                                                                                    | Size of the buffer for the index blocks used by MyISAM tables and shared for all threads.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [key\_cache\_file\_hash\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#key_cache_file_hash_size)                                                                  | 512                                                                                                                                          | -                                                                                                                                          | Number of hash buckets for open and changed files.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [key\_cache\_segments](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#key_cache_segments)                                                                                | 0                                                                                                                                            | -                                                                                                                                          | The number of segments in a key cache. See [Segmented Key Cache](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/system-variables/segmented-key-cache).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| keyring\_operations                                                                                                                                                                                                                                 | -                                                                                                                                            | ON                                                                                                                                         | Whether MySQL 8's keyring operations are enabled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [last\_gtid](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid#last_gtid)                                                                                                                                 | -                                                                                                                                            | empty                                                                                                                                      | MariaDB and MySQL have different [GTID implementations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/gtid).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [local\_infile](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#local_infile)                                                                                                          | ON                                                                                                                                           | OFF                                                                                                                                        | MySQL no longer supports LOAD DATA LOCAL by default.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [lock\_wait\_timeout](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#lock_wait_timeout)                                                                                               | 86400                                                                                                                                        | 31536000                                                                                                                                   | MariaDB has reduced the timeout for acquiring metadata locks.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [log\_bin](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                                      | OFF                                                                                                                                          | ON                                                                                                                                         | MySQL 8 enables the [binary log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log) by default.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [log\_bin\_compress](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                            | OFF                                                                                                                                          | -                                                                                                                                          | MariaDB setting for whether or not the [binary log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log) can be compressed.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| [log\_bin\_compress\_min\_len](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                  | 256                                                                                                                                          | -                                                                                                                                          | Minimum length of sql statement (in statement mode) or record (in row mode) that can be compressed. See [Compressing Events to Reduce Size of the Binary Log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log/compressing-events-to-reduce-size-of-the-binary-log).                                                                                                                                                                                                                                                                                                                                                                                      |
| log\_bin\_use\_v1\_row\_events                                                                                                                                                                                                                      | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variable showing whether or not MySQL's version 2 binary logging format is being used.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [log\_disabled\_statements](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_disabled_statements)                                                                                   | sp                                                                                                                                           | -                                                                                                                                          | Disable logging of certain statements to the [general log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/general-query-log).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| log\_error\_services                                                                                                                                                                                                                                | -                                                                                                                                            | log\_filter\_internal; log\_sink\_internal                                                                                                 | Components to enable for MySQL error logging.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| log\_error\_verbosity                                                                                                                                                                                                                               | -                                                                                                                                            | 3                                                                                                                                          | MySQL variable for setting verbosity of error, warning, and note messages in the error log.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [log\_slave\_updates](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                           | OFF                                                                                                                                          | ON                                                                                                                                         | MySQL 8 has by default enabled [binary logging](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log) of updates a slave receives from a master.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [log\_slow\_admin\_statements](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_slow_admin_statements)                                                                              | ON                                                                                                                                           | OFF                                                                                                                                        | MariaDB logs slow admin statements to the [slow query log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/slow-query-log) by default.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [log\_slow\_disabled\_statements](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_slow_disabled_statements)                                                                        | admin,call,slave,sp                                                                                                                          | -                                                                                                                                          | Disable logging of certain statements to the [slow query log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/slow-query-log).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| [log\_slow\_filter](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_slow_filter)                                                                                                   | admin, filesort, filesort\_on\_disk, full\_join, full\_scan, query\_cache, query\_cache\_miss, tmp\_table, tmp\_table\_on\_disk              | -                                                                                                                                          | For slow query log filtering.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [log\_slow\_rate\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_slow_rate_limit)                                                                                          | 1                                                                                                                                            | -                                                                                                                                          | Limits the number of queries logged to the [slow query log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/slow-query-log).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [log\_slow\_slave\_statements](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                  | ON                                                                                                                                           | OFF                                                                                                                                        | MariaDB logs slow slave statements to the [slow query log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/slow-query-log) by default.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [log\_slow\_verbosity](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_slow_verbosity)                                                                                             | empty                                                                                                                                        | -                                                                                                                                          | Controls information to be added to the [slow query log](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/slow-query-log). See also [Slow Query Log Extended Statistics](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/statistics-for-optimizing-queries/slow-query-log-extended-statistics).                                                                                                                                                                                                                                                                                                        |
| log\_statements\_unsafe\_for\_binlog                                                                                                                                                                                                                | -                                                                                                                                            | ON                                                                                                                                         | MySQL setting for controlling whether binlog warnings are written to the error log.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| log\_syslog\*                                                                                                                                                                                                                                       | platform-dependent                                                                                                                           | -                                                                                                                                          | MySQL variables with settings for writing to syslog.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [log\_tc\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_tc_size)                                                                                                           | 24576                                                                                                                                        | -                                                                                                                                          | Size in bytes of the transaction coordinator log, defined in multiples of 4096.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| log\_throttle\_queries\_not\_using\_indexes                                                                                                                                                                                                         | -                                                                                                                                            | 0                                                                                                                                          | MySQL-only variable for limiting the number of statements without indexes written to the slow query log.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| log\_timestamps                                                                                                                                                                                                                                     | -                                                                                                                                            | UTC                                                                                                                                        | MySQL-only variable controlling the timezone for certain logging conditions.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [log\_warnings](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#log_warnings)                                                                                                          | 2                                                                                                                                            | -                                                                                                                                          | MySQL 8 has replaced with log\_error\_verbosity.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| mandatory\_roles                                                                                                                                                                                                                                    | -                                                                                                                                            | (empty)                                                                                                                                    | MySQL variable for assigning [roles](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/user-account-management/roles) to all users.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| master\_info\_repository                                                                                                                                                                                                                            | -                                                                                                                                            | TABLE                                                                                                                                      | Whether slave logs master status and connection info to a table or a file.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| [max\_allowed\_packet](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_allowed_packet)                                                                                             | 16M                                                                                                                                          | 64M                                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [max\_error\_count](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_error_count)                                                                                                   | 64                                                                                                                                           | 1024                                                                                                                                       | Specifies the maximum number of messages stored for display by [SHOW ERRORS](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/administrative-sql-statements/show/show-errors) and [SHOW WARNINGS](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/administrative-sql-statements/show/show-warnings) statements.                                                                                                                                                                                                                                                                                                                                              |
| max\_execution\_time                                                                                                                                                                                                                                | -                                                                                                                                            | 0                                                                                                                                          | MySQL renamed the max\_statement\_time variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [max\_length\_for\_sort\_data](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_length_for_sort_data)                                                                               | 64                                                                                                                                           | 1024                                                                                                                                       | Used to decide which algorithm to choose when sorting rows. If the total size of the column data, not including columns that are part of the sort, is less than max\_length\_for\_sort\_data, then these are added to the sort key. This can speed up the sort as there's no need to re-read the same row again later. Setting the value too high can slow things down as there will be a higher disk activity for doing the sort.                                                                                                                                                                                                                                                                          |
| [max\_long\_data\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_long_data_size)                                                                                            | 16777216                                                                                                                                     | -                                                                                                                                          | Maximum size for parameter values sent with mysql\_stmt\_send\_long\_data(). Removed in MySQL 5.6.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| max\_points\_in\_geometry                                                                                                                                                                                                                           | -                                                                                                                                            | 65536                                                                                                                                      | Maximum points\_per\_circle for MySQL's ST\_Buffer\_Strategy() function.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [max\_recursive\_iterations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_recursive_iterations)                                                                                 | 4294967295                                                                                                                                   | -                                                                                                                                          | Maximum number of iterations when executing recursive queries.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [max\_relay\_log\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                         | 1073741824                                                                                                                                   | 0                                                                                                                                          | Can be set by session in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [max\_seeks\_for\_key](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_seeks_for_key)                                                                                              | 4294967295                                                                                                                                   | 4294967295 (32-bit) or 18446744073709547520 (64-bit)                                                                                       | The most key seeks required when searching with an index, regardless of the actual index cardinality. If this value is set lower than its default and maximum, indexes will tend to be preferred over table scans.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [max\_session\_mem\_used](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_session_mem_used)                                                                                        | 9223372036854775807                                                                                                                          | -                                                                                                                                          | Amount of memory a single user session is allowed to allocate.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [max\_statement\_time](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_statement_time)                                                                                             | 0                                                                                                                                            | -                                                                                                                                          | Maximum time in seconds that a query can execute before being aborted. MySQL used to have a variable of this name before renaming it max\_execution\_time.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| [max\_tmp\_tables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_tmp_tables)                                                                                                     | 32                                                                                                                                           | -                                                                                                                                          | Unused variable removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [max\_write\_lock\_count](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#max_write_lock_count)                                                                                        | 4294967295                                                                                                                                   | 4294967295 (32-bit) or 18446744073709547520 (64-bit)                                                                                       | Read lock requests will be permitted for processing after this many write locks.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [mrr\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#mrr_buffer_size)                                                                                                   | 262144                                                                                                                                       | -                                                                                                                                          | Size of buffer to use when using multi-range read with range access. See [Multi Range Read optimization](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/mariadb-internal-optimizations/multi-range-read-optimization#range-access).                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [multi\_range\_count](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#multi_range_count)                                                                                               | 1024                                                                                                                                         | -                                                                                                                                          | Unused variable removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [myisam\_block\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#myisam_block_size)                                                                                  | 1024                                                                                                                                         | -                                                                                                                                          | Block size used for [MyISAM](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine) index pages.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [myisam\_recover\_options](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#myisam_recover_options)                                                                        | BACKUP,QUICK                                                                                                                                 | OFF                                                                                                                                        | MyISAM recovery mode.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [myisam\_sort\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#myisam_sort_buffer_size)                                                                     | 134216704                                                                                                                                    | 8388608                                                                                                                                    | Size in bytes of the buffer allocated when creating or sorting indexes on a MyISAM table.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| mysql\_native\_password\_proxy\_users                                                                                                                                                                                                               | -                                                                                                                                            | OFF                                                                                                                                        | Whether MySQL's authentication plugin supports proxy users. I                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [mysql56\_temporal\_format](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-usage/storage-engines/myisam-storage-engine/myisam-system-variables#mysql56_temporal_format)                                                                      | ON                                                                                                                                           |                                                                                                                                            | Causes MariaDB to use the MySQL-5.6 low level formats for [TIME](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/date-and-time-data-types/time), [DATETIME](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/date-and-time-data-types/datetime) and [TIMESTAMP](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/data-types/date-and-time-data-types/timestamp) instead of the [MariaDB 5.3](https://mariadb.com/docs/release-notes/community-server/old-releases/5.3/changes-improvements-in-mariadb-5-3)+ version.                                                                                                                                         |
| new                                                                                                                                                                                                                                                 | -                                                                                                                                            | OFF                                                                                                                                        | Used for backward-compatibility with MySQL 4.1, not present in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| mysqlx+\*                                                                                                                                                                                                                                           | -                                                                                                                                            | \*                                                                                                                                         | MySQL's X plugin related variables.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| ngram\_token\_size                                                                                                                                                                                                                                  | -                                                                                                                                            | 2                                                                                                                                          | Sets the n-gram token size for MySQL's n-gram full-text parser.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| offline\_mode                                                                                                                                                                                                                                       | -                                                                                                                                            | OFF                                                                                                                                        | MySQL settting for specifying whether the server should run in offline mode.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [old\_alter\_table](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#old_alter_table)                                                                                                   | DEFAULT                                                                                                                                      | OFF                                                                                                                                        | From [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103), an alias for [alter\_algorithm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#alter_algorithm).                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [old\_mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#old_mode)                                                                                                                  | Empty string                                                                                                                                 | -                                                                                                                                          | Used for getting MariaDB to emulate behavior from an old version of MySQL or MariaDB. See [OLD Mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/old_mode).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [old\_passwords](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#old_passwords)                                                                                                        | OFF                                                                                                                                          | -                                                                                                                                          | MySQL 8 is no longer compatible with the old pre-MySQL 4.1 form of password hashing.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [optimizer\_selectivity\_sampling\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#optimizer_selectivity_sampling_limit)                                                        | 100                                                                                                                                          | -                                                                                                                                          | Controls number of record samples to check condition selectivity.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [optimizer\_switch](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#optimizer_switch)                                                                                                  | [See details](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#optimizer_switch) |                                                                                                                                            | A series of flags for controlling the query optimizer. MariaDB has introduced a number of new settings.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| optimizer\_trace\_\*                                                                                                                                                                                                                                | -                                                                                                                                            | O\*                                                                                                                                        | MySQL-only variables for optimizer tracing.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [optimizer\_use\_condition\_selectivity](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#optimizer_use_condition_selectivity)                                                          | 1                                                                                                                                            | -                                                                                                                                          | Controls which statistics can be used by the optimizer when looking for the best query execution plan.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| original\_commit\_timestamp                                                                                                                                                                                                                         | -                                                                                                                                            | \*                                                                                                                                         | Used by MySQL 8 for [delaying replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/delayed-replication).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| parser\_max\_mem\_size                                                                                                                                                                                                                              | -                                                                                                                                            | 4294967295 (32-bit) or 18446744073709547520 (64-bit)                                                                                       | MySQL variable for limiting memory available to the parser.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| password\_\*                                                                                                                                                                                                                                        | -                                                                                                                                            | \*                                                                                                                                         | Controls reuse of previous passwords in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [performance\_schema](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/system-tables/performance-schema/performance-schema-system-variables#performance_schema)                                                                             | OFF                                                                                                                                          | ON                                                                                                                                         | The [Performance Schema](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/system-tables/performance-schema) is off by default in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [performance\_schema\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/system-tables/performance-schema/performance-schema-system-variables)                                                                                            |                                                                                                                                              |                                                                                                                                            | Many performance schema variables are autoset in MySQL, and MySQL has a different version, with additional variables.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [plugin\_maturity](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#plugin_maturity)                                                                                                    | One less than the server maturity                                                                                                            | -                                                                                                                                          | Minimum acceptable plugin maturity.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [progress\_report\_time](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#progress_report_time)                                                                                         | 5                                                                                                                                            | -                                                                                                                                          | Time in seconds between sending progress reports to the client for time-consuming statements.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [proxy\_protocol\_networks](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#proxy_protocol_networks)                                                                                   | (empty)                                                                                                                                      | -                                                                                                                                          | Enable [proxy protocol](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/clients-and-utilities/server-client-software/client-libraries/proxy-protocol-support) for these source networks.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| [query\_alloc\_block\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#query_alloc_block_size)                                                                                    | 16384                                                                                                                                        | 8192                                                                                                                                       | Size in bytes of the extra blocks allocated during query parsing and execution (after query\_prealloc\_size is used up).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [query\_cache\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#query_cache_limit)                                                                                                  | \*                                                                                                                                           | -                                                                                                                                          | MySQL has removed the [query cache](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/query-cache).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| [query\_prealloc\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#query_prealloc_size)                                                                                           | 24576                                                                                                                                        | 8192                                                                                                                                       | Size in bytes of the persistent buffer for query parsing and execution, allocated on connect and freed on disconnect.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| range\_optimizer\_max\_mem\_size                                                                                                                                                                                                                    | -                                                                                                                                            | 8388608                                                                                                                                    | MySQL-only variable setting a limit on the range optimizer's memory usage.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| rbr\_exec\_mode                                                                                                                                                                                                                                     | -                                                                                                                                            | STRICT                                                                                                                                     | MySQL-only variable for determining the handling of certain key errors.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| [read\_binlog\_speed\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                    | 0                                                                                                                                            | -                                                                                                                                          | Permits restricting the speed at which the slave reads the binlog from the master.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| regexp\_\*                                                                                                                                                                                                                                          | -                                                                                                                                            | \*                                                                                                                                         | Memory and time limits for regular expression matching operations.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| relay\_log\_info\_repository                                                                                                                                                                                                                        | -                                                                                                                                            | TABLE                                                                                                                                      | MySQL-only variable determining whether the slave's position in the relay logs is written to a file or table.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [replicate\_annotate\_row\_events](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                              | ON                                                                                                                                           | -                                                                                                                                          | Tells the slave to reproduce annotate\_rows\_events received from the master in its own binary log.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [replicate\_do\_db](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                             | empty string                                                                                                                                 | -                                                                                                                                          | See [Dynamic Replication Variables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-filters).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [replicate\_do\_table](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                          | empty string                                                                                                                                 | -                                                                                                                                          | See [Dynamic Replication Variables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-filters).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [replicate\_events\_marked\_for\_skip](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                          | replicate                                                                                                                                    | -                                                                                                                                          | See [Selectively skipping replication of binlog events](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log/selectively-skipping-replication-of-binlog-events).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| [replicate\_ignore\_db](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                         | empty string                                                                                                                                 | -                                                                                                                                          | See [Dynamic Replication Variables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-filters).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [replicate\_ignore\_table](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                      | empty string                                                                                                                                 | -                                                                                                                                          | See [Dynamic Replication Variables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-filters).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [replicate\_wild\_do\_table](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                    | empty string                                                                                                                                 | -                                                                                                                                          | See [Dynamic Replication Variables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-filters).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [replicate\_wild\_ignore\_table](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                | empty string                                                                                                                                 | -                                                                                                                                          | See [Dynamic Replication Variables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-filters).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| require\_secure\_transport                                                                                                                                                                                                                          | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variable determining whether client to server connections need to be secure.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| result\_metadata                                                                                                                                                                                                                                    | -                                                                                                                                            | FULL                                                                                                                                       | Determine whether the server returns result set metadata for connections where this is optional.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [rowid\_merge\_buff\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#rowid_merge_buff_size)                                                                                      | 8388608                                                                                                                                      | -                                                                                                                                          | See [Non-semi-join subquery optimizations](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/subquery-optimizations/non-semi-join-subquery-optimizations).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| rpl\_read\_size                                                                                                                                                                                                                                     | -                                                                                                                                            | 8192                                                                                                                                       | Minimum data in bytes read from the binary and relay log files.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [rpl\_semi\_sync\_\*](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/semisynchronous-replication#system-variables)                                                                                          | -                                                                                                                                            | -                                                                                                                                          | [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103) includes [semisynchronous replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/semisynchronous-replication) without the need to install a plugin.                                                                                                                                                                                                                                                                                                                                                                                              |
| rpl\_stop\_slave\_timeout                                                                                                                                                                                                                           | -                                                                                                                                            | 31536000                                                                                                                                   | Controls the time that [STOP SLAVE](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/administrative-sql-statements/replication-statements/stop-replica) waits before timing out.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| schema\_definition\_cache                                                                                                                                                                                                                           | -                                                                                                                                            | 256                                                                                                                                        | Limits the number of schema definition objects kept in the dictionary object cache.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [secure\_auth](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#secure_auth)                                                                                                            | ON                                                                                                                                           | -                                                                                                                                          | Removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [secure\_timestamp](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#secure_timestamp)                                                                                                  | NO                                                                                                                                           | -                                                                                                                                          | MariaDB-only option permitting the restricting of direct setting of a session timestamp..                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| server\_id\_bits                                                                                                                                                                                                                                    | -                                                                                                                                            | server\_id                                                                                                                                 | MySQL-only variable for use in MySQL Cluster.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| server\_uuid                                                                                                                                                                                                                                        | -                                                                                                                                            | UUID                                                                                                                                       | MySQL-only variable containing the UUID.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| session\_track\_gtids                                                                                                                                                                                                                               | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variables for tracking gtid changes. MariaDB and MySQL's gtid implementation is different.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| sha256\_password\_proxy\_users                                                                                                                                                                                                                      | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variable determining whether the sha256\_password plugin supports proxy users.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| show\_create\_table\_verbosity                                                                                                                                                                                                                      | -                                                                                                                                            | OFF                                                                                                                                        | Option to cause [SHOW CREATE TABLE](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/administrative-sql-statements/show/show-create-table) to display ROW\_FORMAT in all cases.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| show\_old\_temporals                                                                                                                                                                                                                                | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only variable for determining whether SHOW CREATE TABLE output should include comments for old format temporal columns.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| [skip\_parallel\_replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                   | OFF                                                                                                                                          | -                                                                                                                                          | See [parallel replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [skip\_replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                             | OFF                                                                                                                                          | -                                                                                                                                          | See [Selectively skipping replication of binlog events](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/server-monitoring-logs/binary-log/selectively-skipping-replication-of-binlog-events).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| slave\_allow\_batching                                                                                                                                                                                                                              | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| slave\_checkpoint\_group                                                                                                                                                                                                                            | -                                                                                                                                            | 512                                                                                                                                        | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| slave\_checkpoint\_period                                                                                                                                                                                                                           | -                                                                                                                                            | 300                                                                                                                                        | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [slave\_ddl\_exec\_mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                        | IDEMPOTENT                                                                                                                                   | -                                                                                                                                          | Modes for how replication of DDL events should be executed.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [slave\_domain\_parallel\_threads](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                              | 0                                                                                                                                            | -                                                                                                                                          | For configuring [parallel replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication#configuration-variable-slave_domain_parallel_threads).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [slave\_net\_timeout](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                           | 3600                                                                                                                                         | 60                                                                                                                                         | MySQL reduced the timeout to 60s.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [slave\_parallel\_max\_queued](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                  | 131072                                                                                                                                       | -                                                                                                                                          | For configuring [parallel replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication#configuration-variable-slave_domain_parallel_threads).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [slave\_parallel\_mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                         | conservative                                                                                                                                 | -                                                                                                                                          | Controls what transactions are applied in parallel when using [parallel\_replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [slave\_parallel\_threads](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                      | 0                                                                                                                                            | -                                                                                                                                          | For configuring [parallel replication](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/parallel-replication#configuration-variable-slave_domain_parallel_threads).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| slave\_parallel\_type                                                                                                                                                                                                                               | -                                                                                                                                            | DATABASE                                                                                                                                   | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| slave\_pending\_jobs\_size\_max                                                                                                                                                                                                                     | -                                                                                                                                            | 16777216                                                                                                                                   | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| slave\_preserve\_commit\_order                                                                                                                                                                                                                      | -                                                                                                                                            | OFF                                                                                                                                        | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| slave\_rows\_search\_algorithms                                                                                                                                                                                                                     | -                                                                                                                                            | INDEX\_SCAN, HASH\_SCAN                                                                                                                    | MySQL-only replication variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [slave\_run\_triggers\_for\_rbr](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                | NO                                                                                                                                           |                                                                                                                                            | See [Running triggers on the slave for Row-based events](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/running-triggers-on-the-replica-for-row-based-events) for a description and use-case for this setting.                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| [slave\_transaction\_retry\_errors](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                             | 1213,1205                                                                                                                                    | -                                                                                                                                          | When an error occurs during a transaction on the slave, replication usually halts. By default, transactions that caused a deadlock or elapsed lock wait timeout will be retried. One can add other errors to the list of errors that should be retried by adding a comma-separated list of error numbers to this variable.                                                                                                                                                                                                                                                                                                                                                                                  |
| [slave\_transaction\_retry\_interval](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                           | 0                                                                                                                                            | -                                                                                                                                          | Interval in seconds for the slave SQL thread to retry a failed transaction due to a deadlock, elapsed lock wait timeout or an error listed in slave\_transaction\_retry\_errors.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [sort\_buffer\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#sort_buffer_size)                                                                                                 | 2097152                                                                                                                                      | 262144                                                                                                                                     | The default sort buffer allocated has been reduced in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [sql\_mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#sql_mode)                                                                                                                  | STRICT\_TRANS\_TABLES, ERROR\_FOR\_DIVISION\_BY\_ZERO, NO\_AUTO\_CREATE\_USER, NO\_ENGINE\_SUBSTITUTION                                      | ONLY\_FULL\_GROUP\_BY, STRICT\_TRANS\_TABLES, NO\_ZERO\_IN\_DATE, NO\_ZERO\_DATE, ERROR\_FOR\_DIVISION\_BY\_ZERO, NO\_ENGINE\_SUBSTITUTION | See [SQL Mode](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/sql_mode).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| ssl\_fips\_mode                                                                                                                                                                                                                                     | -                                                                                                                                            | OFF                                                                                                                                        | Whether FIPS mode is enabled on the server side.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [standard\_compliant\_cte](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#standard_compliant_cte)                                                                                     | ON                                                                                                                                           | -                                                                                                                                          | See [Common Table Expressions](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-statements/data-manipulation/selecting-data/common-table-expressions).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [storage\_engine](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#storage_engine)                                                                                                      | InnoDB                                                                                                                                       | -                                                                                                                                          | Alias for [default\_storage\_engine](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#default_storage_engine), removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [strict\_password\_validation](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#strict_password_validation)                                                                             | ON                                                                                                                                           | -                                                                                                                                          | In MariaDB, when password validation plugins are enabled, reject passwords that cannot be validated (passwords specified as a hash).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| stored\_program\_definition\_cache                                                                                                                                                                                                                  | -                                                                                                                                            | 256                                                                                                                                        | Limits the number of stored program definition objects kept in the dictionary object cache.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| super\_read\_only                                                                                                                                                                                                                                   | -                                                                                                                                            | OFF                                                                                                                                        | MySQL variable for prohibiting client updates from users with the SUPER privilege.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [sync\_binlog](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/standard-replication/replication-and-binary-log-system-variables)                                                                                                  | 0                                                                                                                                            | 1                                                                                                                                          | MySQL synchronizes all actions to the binary log before they are committed.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [sync\_frm](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#sync_frm)                                                                                                                  | 1                                                                                                                                            | -                                                                                                                                          | .frm files have been removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| [system\_versioning\_alter\_history](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-structure/temporal-tables/system-versioned-tables#system_versioning_alter_history)                                                                | ERROR                                                                                                                                        | -                                                                                                                                          | MariaDB has [System-Versioned Tables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-structure/temporal-tables/system-versioned-tables)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [system\_versioning\_asof](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-structure/temporal-tables/system-versioned-tables#system_versioning_asof)                                                                                   | DEFAULT                                                                                                                                      | -                                                                                                                                          | MariaDB has [System-Versioned Tables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-structure/temporal-tables/system-versioned-tables)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [table\_definition\_cache](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#table_definition_cache)                                                                                     | 400                                                                                                                                          | -1 (autosized)                                                                                                                             | Number of table definitions that can be cached.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [table\_open\_cache\_instances](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#table_open_cache_instances)                                                                            | 8                                                                                                                                            | 16                                                                                                                                         | Maximum number of table cache instances.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| tablespace\_definition\_cache                                                                                                                                                                                                                       | -                                                                                                                                            | 256                                                                                                                                        | Limits the number of tablespace definition objects kept in the dictionary object cache.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| [tcp\_keepalive\_interval](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tcp_keepalive_interval)                                                                                     | 0                                                                                                                                            | -                                                                                                                                          | Interval, in seconds, between when successive keep-alive packets are sent if no acknowledgement is received.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| [tcp\_keepalive\_probes](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tcp_keepalive_probes)                                                                                         | 0                                                                                                                                            | -                                                                                                                                          | Number of unacknowledged probes to send before considering the connection dead and notifying the application layer.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [tcp\_keepalive\_time](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tcp_keepalive_time)                                                                                             | 0                                                                                                                                            | -                                                                                                                                          | Timeout, in milliseconds, with no activity until the first TCP keep-alive packet is sent.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| temptable\_max\_ram                                                                                                                                                                                                                                 | -                                                                                                                                            | 1GB                                                                                                                                        | Limits the RAM used by MySQL's TempTable storage engine.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [thread\_cache\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#thread_cache_size)                                                                                               | Autosized                                                                                                                                    | -1 (autosized)                                                                                                                             | MariaDB uses an [improved thread pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [thread\_concurrency](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#thread_concurrency)                                                                                              | 10                                                                                                                                           | -                                                                                                                                          | Removed in MySQL 5.7.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [thread\_pool\_idle\_timeout](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                 | 60                                                                                                                                           | -                                                                                                                                          | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [thread\_pool\_max\_threads](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                  | 65536                                                                                                                                        | -                                                                                                                                          | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [thread\_pool\_min\_threads](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                  | 1                                                                                                                                            | -                                                                                                                                          | Windows-only. See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [thread\_pool\_oversubscribe](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                 | 3                                                                                                                                            | -                                                                                                                                          | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [thread\_pool\_prio\_kickup](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                  | auto                                                                                                                                         | -                                                                                                                                          | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [thread\_pool\_priority](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                      | auto                                                                                                                                         | -                                                                                                                                          | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [thread\_pool\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                          | Number of processors                                                                                                                         | 16\*                                                                                                                                       | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb). \*Only available in MySQL with a commercial plugin.                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [thread\_pool\_stall\_limit](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-system-status-variables)                                                  | 500                                                                                                                                          | 6\*                                                                                                                                        | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb). \*Only available in MySQL with a commercial plugin.                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [thread\_stack](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#thread_stack)                                                                                                          | 299008                                                                                                                                       | Varies                                                                                                                                     | See [Using the Thread Pool](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/buffers-caches-and-threads/thread-pool/thread-pool-in-mariadb).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [time\_format](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#time_format)                                                                                                            | %H:%i:%s                                                                                                                                     | -                                                                                                                                          | Removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| [timed\_mutexes](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#timed_mutexes)                                                                                                        | OFF                                                                                                                                          | -                                                                                                                                          | Removed in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| tls\_version                                                                                                                                                                                                                                        | -                                                                                                                                            | Varies                                                                                                                                     | MySQL-only variable showing the permitted tls protocols.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [tmp\_disk\_table\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tmp_disk_table_size)                                                                                          | 18446744073709551615                                                                                                                         | -                                                                                                                                          | Max size for data for an internal temporary on-disk MyISAM or Aria table.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| [tmp\_memory\_table\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tmp_memory_table_size)                                                                                      | 16777216                                                                                                                                     | -                                                                                                                                          | Alias for [tmp\_table\_size](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tmp_table_size).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| transaction\_allow\_batching                                                                                                                                                                                                                        | -                                                                                                                                            | OFF                                                                                                                                        | Variable for enabling batching of statements within the same transaction in MySQL Cluster.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| transaction\_isolation                                                                                                                                                                                                                              | -                                                                                                                                            | REPEATABLE-READ                                                                                                                            | The MariaDB equivalent is [tx\_isolation](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tx_isolation).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| transaction\_read\_only                                                                                                                                                                                                                             | -                                                                                                                                            | OFF                                                                                                                                        | The MariaDB equivalent is [tx\_read\_only](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tx_read_only).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| transaction\_write\_set\_extraction                                                                                                                                                                                                                 | -                                                                                                                                            | OFF                                                                                                                                        | Unused MySQL-only variable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [tx\_isolation](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tx_isolation)                                                                                                          | REPEATABLE-READ                                                                                                                              | -                                                                                                                                          | The MySQL equivalent is transaction\_isolation.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [tx\_read\_only](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#tx_read_only)                                                                                                         | OFF                                                                                                                                          | -                                                                                                                                          | The MySQL equivalent is transaction\_read\_only.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| [use\_stat\_tables](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#use_stat_tables)                                                                                                   | NEVER                                                                                                                                        | -                                                                                                                                          | Controls the use of [engine-independent table statistics](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/statistics-for-optimizing-queries/engine-independent-table-statistics).                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [userstat](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#userstat)                                                                                                                   | OFF                                                                                                                                          | -                                                                                                                                          | Whether to activate MariaDB's [User Statistics](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/ha-and-performance/optimization-and-tuning/query-optimizations/statistics-for-optimizing-queries/user-statistics) implementation, not available in MySQL.                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| version\_compile\_zlib                                                                                                                                                                                                                              | -                                                                                                                                            | \*                                                                                                                                         | Version of the zlib library compiled in.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [version\_malloc\_library](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#version_malloc_library)                                                                                     | \*                                                                                                                                           | -                                                                                                                                          | Version of the used malloc library.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [version\_source\_revision](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/server-management/variables-and-modes/server-system-variables#version_source_revision)                                                                                   | Varies                                                                                                                                       | -                                                                                                                                          | Permits seeing exactly which version of the source was used for a build.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| [version\_ssl\_library](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/security/encryption/data-in-transit-encryption/ssltls-system-variables)                                                                                                      | \*                                                                                                                                           | -                                                                                                                                          | Version of the used TLS library.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| windowing\_high\_use\_precision                                                                                                                                                                                                                     | -                                                                                                                                            | \*                                                                                                                                         | MySQL option allowing safety to be sacrificed for speed in [window function](https://app.gitbook.com/s/SsmexDFPv2xG2OTyO5yV/reference/sql-functions/special-functions/window-functions) calculations.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| [wsrep\_\*](https://app.gitbook.com/s/3VYeeVGUV4AMqrA3zwy7/reference/galera-cluster-system-variables)                                                                                                                                               | \*                                                                                                                                           | -                                                                                                                                          | [Galera cluster](https://github.com/mariadb-corporation/docs-release-notes/blob/test/kb/en/mariadb-galera-cluster/README.md) is only available in MariaDB.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Variable                                                                                                                                                                                                                                            | [MariaDB 10.3](https://mariadb.com/docs/release-notes/community-server/old-releases/10.3/what-is-mariadb-103)                                | MySQL 8.0                                                                                                                                  | Notes                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |

## See Also

* [System Variable Differences Between MariaDB 10.3 and MySQL 5.7](https://mariadb.com/docs/release-notes/community-server/about/compatibility-and-differences/system-variable-differences-between-mariadb-and-mysql/system-variable-differences-between-mariadb-and-mysql-unmaintained-series/system-variable-differences-between-mariadb-10-3-and-mysql-5-7)

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