From: Alvaro Herrera <alvherre@commandprompt.com>
To: Michal Szymanski <szymanskim@datera.pl>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Big problem with sql update operation
Date: Fri, 25 May 2007 18:38:28 -0400
Message-ID: <20070525223828.GE24789@alvh.no-ip.org> (raw)
In-Reply-To: <465762B6.3080608@datera.pl>
References: <4656A4E0.7020400@datera.pl>
<8751.1180103318@sss.pgh.pa.us>
<465762B6.3080608@datera.pl>
Michal Szymanski wrote:
> Tom Lane wrote:
> >(For the record, the reason you see nonlinear degradation is the
> >accumulation of tentatively-dead versions of the row, each of which has
> >to be rechecked by each later update.)
> >
> There is another strange thing. We have two versions of our test
> environment one with production DB copy and second genereated with
> minimal data set and it is odd that update presented above on copy of
> production is executing 170ms but on small DB it executing 6s !!!!
How are you vacuuming the tables?
--
Alvaro Herrera http://www.advogato.org/person/alvherre
"El conflicto es el camino real hacia la unión"
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To: pgsql-performance@postgresql.org
Cc: alvherre@commandprompt.com, szymanskim@datera.pl, tgl@sss.pgh.pa.us
Subject: Re: Big problem with sql update operation
In-Reply-To: <20070525223828.GE24789@alvh.no-ip.org>
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