Re: Problems with autovacuum - Mailing list pgsql-performance

From Alvaro Herrera
Subject Re: Problems with autovacuum
Date
Msg-id 20090526181934.GG32650@alvh.no-ip.org
Whole thread Raw
In response to Re: Problems with autovacuum  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Problems with autovacuum
List pgsql-performance
Tom Lane escribió:
> =?UTF-8?B?xYF1a2FzeiBKYWdpZcWCxYJv?= <lukasz.jagiello@gforces.pl> writes:
> > That autovacuum working hole time, shoudn't be run only when db needs ?
>
> With 2000 databases to cycle through, autovac is going to be spending
> quite a lot of time just finding out whether it needs to do anything.
> I believe the interpretation of autovacuum_naptime is that it should
> examine each database that often, ie once a minute by default.  So
> it's got more than 30 databases per second to look through.

Note that this is correct in 8.1 and 8.2 but not 8.3 onwards.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

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