evs.user_send_window
This page is part of MariaDB's Documentation.
The parent of this page is: wsrep Provider Options for MariaDB Enterprise Server
Topics on this page:
Overview
Defines the maximum number of data packets the node uses at a time in replication
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 evs.user_wsrep_provider_options
.
See also: wsrep Provider Options for MariaDB Enterprise Server 11.4, in 10.6 ES, 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
DETAILS
The evs.user_send_window
option determines the maximum number of data packets the node uses at a time in replication.
You must use a value that is smaller than evs.send_window
. The recommended value is half evs.send_
For clusters implemented over WAN, you can set this to a value considerably higher, (for example, 512) than cluster implementations over LAN.
Attribute | Value |
---|---|
Option Name | evs.user_send_window |
Default Value | 2 |
Dynamic | YES |
Debug |
|
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_
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='evs.user_send_window=5;gcache.debug=YES;gcs.fc_limit=NO;socket.send_buf_size=NO;evs.keepalive_period=PT3S'
Set Dynamically
Changes made dynamically with SET GLOBAL
are not durable and will be lost when the server is stopped. To be durable, changes must be set in the configuration file.
The evs.user_send_window option can be set dynamically using the SET GLOBAL
command. Setting wsrep_provider_options
dynamically does not change the value of other wsrep_provider_options
.
To set evs.user_send_window dynamically:
SET GLOBAL wsrep_provider_options='evs.user_send_window=5';
To dynamically set multiple options in a single statement:
SET GLOBAL wsrep_provider_options='evs.user_send_window=5;cert.optimistic_pa=NO';
CHANGE HISTORY
Release Series | History |
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11.4 Enterprise |
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10.6 Enterprise |
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10.6 Community |
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10.5 Enterprise |
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10.5 Community |
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10.4 Enterprise |
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10.4 Community |
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10.3 Enterprise |
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10.3 Community |
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10.2 Enterprise |
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10.2 Community |
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