From: Gunther Mayer <gunther.mayer@googlemail.com>
To: pgsql-performance@postgresql.org
Subject: Re: VERY slow queries at random
Date: Thu, 07 Jun 2007 16:22:47 +0200
Message-ID: <466814B7.6000606@gmail.com> (raw)
In-Reply-To: <20070606195649.GG11545@phlogiston.dyndns.org>
References: <46670916.9090505@gmail.com>
<20070606195649.GG11545@phlogiston.dyndns.org>
Andrew Sullivan wrote:
> On Wed, Jun 06, 2007 at 09:20:54PM +0200, Gunther Mayer wrote:
>
>> What the heck could cause such erratic behaviour? I suspect some type of
>> resource problem but what and how could I dig deeper?
>>
>
> Is something (perhaps implicitly) locking the table? That will cause
> this.
>
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. No explicit locking
is done anywhere, but perhaps you're right and it is a locking issue.
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?
Gunther
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To: pgsql-performance@postgresql.org
Cc: gunther.mayer@googlemail.com
Subject: Re: VERY slow queries at random
In-Reply-To: <466814B7.6000606@gmail.com>
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