maria-discuss team mailing list archive

[Nils Carlson <pyssling@xxxxxxxxxxx>]

Hi,

I've been working on developing a pacemaker resource-agent for mariadb 
semi-sync replication.
There is a pull request here on github:

https://github.com/ClusterLabs/resource-agents/pull/929

I would be very happy for some review (and even testing) of this 
resource-agent from somebody with expertise in mariadb replication.

The general idea is to select the master at startup and failure as the 
node with the highest GTID.
AFTER_SYNC is used to ensure at least one slave will have all the 
updates.
mariadb is started with --log-slave-updates to ensure that slaves log 
all events, so the binary log on each node should always be complete.

The parameter set on each node is as follows:

SET GLOBAL rpl_semi_sync_slave_enabled='ON', \
                           rpl_semi_sync_master_enabled='ON', \
                           rpl_semi_sync_master_wait_point='AFTER_SYNC', 
\
                           gtid_strict_mode='ON', \
                           sync_binlog=1, \
                           sync_master_info=1, \
                           sync_relay_log=1, \
                           sync_relay_log_info=1;

I suspect this may be overkill, but I don't have the competence to 
judge.

I have also found that calling "SHOW SLAVE STATUS;" may take a long time 
to display data when the slave is very busy (typically replicating after 
a failure). Is there any way to make sure it doesn't block?

All feedback very welcome.

Best Regards,
Nils Carlson