Rechercher dans le manuel MySQL
17.3.11.3 Semisynchronous Replication Monitoring
The plugins for the semisynchronous replication capability expose several system and status variables that you can examine to determine its configuration and operational state.
The system variable reflect how semisynchronous replication is
configured. To check their values, use SHOW
VARIABLES
:
The status variables enable you to monitor the operation of
semisynchronous replication. To check their values, use
SHOW STATUS
:
When the master switches between asynchronous or semisynchronous
replication due to commit-blocking timeout or a slave catching
up, it sets the value of the
Rpl_semi_sync_master_status
status variable appropriately. Automatic fallback from
semisynchronous to asynchronous replication on the master means
that it is possible for the
rpl_semi_sync_master_enabled
system variable to have a value of 1 on the master side even
when semisynchronous replication is in fact not operational at
the moment. You can monitor the
Rpl_semi_sync_master_status
status variable to determine whether the master currently is
using asynchronous or semisynchronous replication.
To see how many semisynchronous slaves are connected, check
Rpl_semi_sync_master_clients
.
The number of commits that have been acknowledged successfully
or unsuccessfully by slaves are indicated by the
Rpl_semi_sync_master_yes_tx
and Rpl_semi_sync_master_no_tx
variables.
On the slave side,
Rpl_semi_sync_slave_status
indicates whether semisynchronous replication currently is
operational.
Document created the 26/06/2006, last modified the 26/10/2018
Source of the printed document:https://www.gaudry.be/en/mysql-rf-replication-semisync-monitoring.html
The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.
References
These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.