Date: Tue, 12 Jun 2007 12:08:02 -0400
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Sabin Coanda <sabin.coanda@deuromedia.ro>
Cc: pgsql-performance@postgresql.org
Subject: Re: VACUUM vs auto-vacuum daemon
Message-ID: <20070612160802.GC15517@alvh.no-ip.org>
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Sabin Coanda wrote:
> Hi there,
> 
> Using explicitly VACUUM command give me the opportunity to fine tune my 
> VACUUM scheduling parameters, after I analyze the log generated by VACUUM 
> VERBOSE.
> 
> On the other hand I'd like to use the auto-vacuum mechanism because of its 
> facilities. Unfortunately, after I made some initial estimations for 
> autovacuum_naptime, and I set the specific data into pg_autovacuum table, I 
> have not a feedback from the auto-vacuum mechanism to check that it works 
> well or not.  It would be nice to have some kind of log similar with the one 
> generated by VACUUM VERBOSE. Is the auto-vacuum mechanism able to provide 
> such a useful log ?

No, sorry, autovacuum is not currently very good regarding reporting its
activities.  It's a lot better in 8.3 but even there it doesn't report
the full VACUUM VERBOSE log.  It looks like this:

LOG:  automatic vacuum of table "alvherre.public.foo": index scans: 0
        pages: 45 removed, 0 remain
        tuples: 10000 removed, 0 remain
        system usage: CPU 0.00s/0.00u sec elapsed 0.01 sec
LOG:  automatic analyze of table "alvherre.public.foo" system usage: CPU 0.00s/0.00u sec elapsed 0.00 sec

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