Re: Long-running performance (MVCC, Vacuum, etc.) - Any fix?

[Vivek Khera <khera(at)kcilink(dot)com>]

>>>>> "MvO" == Martijn van Oosterhout <kleptog(at)svana(dot)org> writes:

MvO> I'd suggest, use the autovacuum daemon, tune your FSM settings to what
MvO> you expect the load to be and maybe schedule a database-wide
MvO> REINDEX/VACUUM FULL regularly. We found doing it once a month was
MvO> enough to keep it tip-top over the long term...

If you know your application usage patterns well, scheduling vacuum
via cron probably would be better than autovacuum.  autovacuum runs
whenever it pleases, and doesn't deal well with extremely large tables
(ie, it never runs vacuum on them since the % change may be small even
though millions of rows are "expired").  You can even vacuum differnt
tables on different schedules.  Just make sure the VACUUMs don't 
overlap!

I haven't run reindex or vacuum full since I upgraded to 7.4.x.  The
indexes are not bloating, and sufficient calls to vacuum keep the
"stable set size" of the db pretty constant.  ie, it doesn't grow
without bounds, as the OP fears.

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Vivek Khera, Ph.D.                Khera Communications, Inc.
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