gcs.recv_q_soft_limit

Overview

Specifies the fraction of gcs.recv_q_hard_limit after which replication rate will be throttled

The wsrep_provider_options system variable applies to MariaDB Enterprise Cluster, powered by Galera and to Galera Cluster available with MariaDB Community Server. This page relates specifically to the gcs.recv_q_soft_limit wsrep_provider_options.

See also: wsrep Provider Options for MariaDB Enterprise Server 10.6, in 10.5 ES, in 10.4 ES, in 10.3 ES, in 10.2 ES, in 10.6 CS, in 10.5 CS, in 10.4 CS, in 10.3 CS, and in 10.2 CS

USAGE

DETAILS

The degree of throttling is a linear function of recv queue size and goes from 1.0 (full rate) at gcs.recv_q_soft_limit to gcs.max_throttle at gcs.recv_q_hard_limit. The full rate, as estimated between 0 and gcs.recv_q_soft_limit is an imprecise estimate of a regular replication rate.

Attribute

Value

Option Name

gcs.recv_q_soft_limit

Default Value

0.25

Dynamic

NO

Debug

NO

SYNONYMS

SCHEMA

PARAMETERS

SKYSQL

PRIVILEGES

EXAMPLES

Display Current Value

wsrep_provider_options define optional settings the node passes to the wsrep provider.

To display current wsrep_provider_options values:

SHOW GLOBAL VARIABLES LIKE 'wsrep_provider_options';

The expected output will display the option and the value. Options with no default value, for example SSL options, will not be displayed in the output.

Set in Configuration File

When changing a setting for a wsrep_provider_options in the config file, you must list EVERY option that is to have a value other than the default value. Options that are not explicitly listed are reset to the default value.

Options are set in the my.cnf configuration file. Use the ; delimiter to set multiple options.

The configuration file must be updated on each node. A restart to each node is needed for changes to take effect.

Use a quoted string that includes every option where you want to override the default value. Options that are not in the list will reset to their default value.

To set the option in the configuration file:

wsrep_provider_options='gcs.recv_q_soft_limit=0.30;gcache.debug=YES;gcs.fc_limit=NO;socket.send_buf_size=NO;evs.keepalive_period=PT3S'

Set Dynamically

The gcs.recv_q_soft_limit option cannot be set dynamically. It can only be set in the configuration file.

Trying to change a non-dynamic option with SET results in an error:

ERROR 1210 (HY000): Incorrect arguments to SET

ERROR HANDLING

FEATURE INTERACTION

RESPONSES

DIAGNOSIS

ISO 9075:2016

CHANGE HISTORY

Release Series

History

10.6 Enterprise

  • Present starting in MariaDB Enterprise Server 10.6.4-1.

10.6 Community

  • Present starting in MariaDB Community Server 10.6.0.

10.5 Enterprise

  • Present starting in MariaDB Enterprise Server 10.5.3-1.

10.5 Community

  • Present starting in MariaDB Community Server 10.5.0.

10.4 Enterprise

  • Present starting in MariaDB Enterprise Server 10.4.6-1.

10.4 Community

  • Present starting in MariaDB Community Server 10.4.0.

10.3 Enterprise

  • Present starting in MariaDB Enterprise Server 10.3.16-1.

10.3 Community

  • Present starting in MariaDB Community Server 10.3.0.

10.2 Enterprise

  • Present starting in MariaDB Enterprise Server 10.2.25-1.

10.2 Community

  • Present starting in MariaDB Community Server 10.2.0.

EXTERNAL REFERENCES