From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-performance@postgresql.org
Subject: Re: VERY slow queries at random
Date: Thu, 7 Jun 2007 11:45:50 -0400
Message-ID: <20070607154550.GF14087@phlogiston.dyndns.org> (raw)
In-Reply-To: <466814B7.6000606@gmail.com>
References: <46670916.9090505@gmail.com>
<20070606195649.GG11545@phlogiston.dyndns.org>
<466814B7.6000606@gmail.com>
On Thu, Jun 07, 2007 at 04:22:47PM +0200, Gunther Mayer wrote:
> There are a whole bunch of update queries that fire all the time but
> afaik none of them ever lock the entire table. To the best of my
> knowledge UPDATE ... WHERE ... only locks those rows that it actually
> operates on, in my case this is always a single row.
Well that shouldn't be biting you, then (you're not in SERIALIZABLE
mode, right?). The other obvious bit would be checkpoint storms.
What's your bgwriter config like?
> Question is, how do I find out about locks at the time when I only get
> told about the slow query *after* it has completed and postgres has told
> me so by logging a slow query entry in my logs?
You can't :(
A
--
Andrew Sullivan | ajs@crankycanuck.ca
This work was visionary and imaginative, and goes to show that visionary
and imaginative work need not end up well.
--Dennis Ritchie
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To: pgsql-performance@postgresql.org
Cc: ajs@crankycanuck.ca
Subject: Re: VERY slow queries at random
In-Reply-To: <20070607154550.GF14087@phlogiston.dyndns.org>
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