>> You mean running a VACUUM statement manually? I would basically try to
>> avoid such a situation as the way I see it, the database should be
>> configured in such a manner that it will be able to handle the load at
>> any given moment and so I wouldn't want to manually intervene here. If
>> you think differently, I'll be happy to stand corrected.
>
> I do think differently.
>
> Autovacuum isn't perfect, and you shouldn't make it too aggressive
> since it does generate a lot of I/O activity. If you can pick a time
> where it will be able to run without interfering too much, running
> vacuum "manually" (where manually could easily be a cron task, ie,
> automatically but coming from outside the database software itself),
> you'll be able to dial down autovacuum and have more predictable load
> overall.
>
Something specific that you refer to in autovacuum's non-perfection, that is, what types of issues are you aware of?
As for the I/O - this is indeed true that it can generate much activity, but the way I see it, if you run performance
testsand the tests succeed in all parameters even with heavy I/O, then you are good to go. That is, I don't mind the
serverdoing lots of I/O as long as it's not causing lags in processing the messages that it handles.
Thanks,
Ofer