----- Original Message -----
> From: "Rafał Radecki" <radecki.rafal@stripped>
>
> Seconds_Behind_Master: 364
>
> So if I have rpl_semi_sync_master_timeout=5000 (5s) and semisync
>
> why is it possible on the slave to fall behind the master?
Semi-sync only guarantees that the slave has *received* the statement in it's relay log.
The rpl_semi_sync_master_timeout value is the timeout for the slave to acknowledge this,
whereas the Seconds_Behind_Master value gives an indication of how far statement
*execution* is lagging.
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