mysql - tracking the slave lag -
i have master-master setup , noticed active master can handle several simultaneous queries @ time while slave reads 1 query @ time , takes lot of time catch up.
1) there solution this?
2) why slave shows 0 seconds "seconds_behind_maser". there times when shows correct number of seconds behind. in case, showing 0 seconds while still reading log.
3) why mmm_control shows both masters online while expected 1 master in "awaiting recovery" state.
for master doesnt matter order simultanious updates/rollbacks/timeouts etc take place. whatever did resolve conflict right , clients given correct feedback.
the slave must execute updates in same order master, way acheive run updates sequentially in order master commited them. not must single thread, can start work after master has commited. means when commit log record flushed disk, there actual physical io wait for.
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