Subject: Re: 12 hour table vacuums
From: Csaba Nagy <nagy@ecircle-ag.com>
To: Ron St-Pierre <ron.pgsql@shaw.ca>
Cc: pgsql-performance@postgresql.org
In-Reply-To: <471E18ED.3090704@shaw.ca>
References: <471E18ED.3090704@shaw.ca>
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Date: Tue, 23 Oct 2007 18:21:16 +0200
Message-Id: <1193156476.21016.55.camel@PCD12478>
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On Tue, 2007-10-23 at 08:53 -0700, Ron St-Pierre wrote:
> [snip] We were running autovacuum but it interfered with 
> the updates to we shut it off.

This is not directly related to your question, but it might be good for
your DB: you don't need to turn off autovacuum, you can exclude tables
individually from being autovacuumed by inserting the appropriate rows
in pg_autovacuum. See:

http://www.postgresql.org/docs/8.1/static/catalog-pg-autovacuum.html

We also do have here a few big tables which we don't want autovacuum to
touch, so we disable them via pg_autovacuum. There are a few really big
ones which change rarely - those we only vacuum via a DB wide vacuum in
the weekend (which for us is a low activity period). If you say your
table is only changed rarely, you might be OK too with such a setup...

Cheers,
Csaba.