MySQL on Galera

[solracsf]

Clusters are complicated because of atomicity of transactions; but can Galera wrep_sync_wait help here?

Either by setting it globally server side (SET GLOBAL wsrep_sync_wait = 1 (or 7)), or by issue these command by juicefs internals directly when galera is detected?

SET SESSION wsrep_sync_wait=1; SELECT ...; SET SESSION wsrep_sync_wait=0;

See https://mariadb.com/kb/en/galera-cluster-system-variables/#wsrep_sync_wait

[davies]

@solracsf It seems that the server side configuration will be better, so we don't need to change JuiceFS for a special deployment.

In the other way, we could use this trick to implement the transaction for MariaDB in the MySQL driver other than in JuiceFS.