Message-ID: <46F7D207.3000901@nekomancer.net>
Date: Mon, 24 Sep 2007 17:04:39 +0200
From: =?ISO-8859-1?Q?G=E1bor_Farkas?= <gabor@nekomancer.net>
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To: Heikki Linnakangas <heikki@enterprisedb.com>
CC: pgsql-performance@postgresql.org
Subject: Re: select count(*) performance (vacuum did not help)
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	<46F7C9F1.1080805@enterprisedb.com>
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Heikki Linnakangas wrote:
> Gábor Farkas wrote:
>> - but in the past, the cron-job was not in place, so the table's size
>> grew to around 800000 entries (in around 80 days)
> 
> That bloated your table, so that there's still a lot of empty pages in
> it. VACUUM FULL should bring it back to a reasonable size. Regular
> normal non-FULL VACUUMs should keep it in shape after that.
> 

hmm... can a full-vacuum be performed while the database is still "live" 
(i mean serving requests)?

will the db still be able to respond to queries?

or in a different way:

if i do a full vacuum to that table only, will the database still serve 
data from the other tables at a normal speed?

thanks,
gabor