From: Scott Marlowe <scott.marlowe@gmail.com>
To: Thomas Zaksek <zaksek@ptt.uni-due.de>
Cc: pgsql-performance@postgresql.org
Subject: Re: Join Query Perfomance Issue
Date: Wed, 13 Feb 2008 15:36:07 -0600
Message-ID: <dcc563d10802131336s366d66c6kcb9f1fd23818552b@mail.gmail.com> (raw)
In-Reply-To: <47B170BF.5000206@ptt.uni-due.de>
References: <47B08F19.8000500@ptt.uni-due.de>
<dcc563d10802111337x2e19d2e4n74979077125079f1@mail.gmail.com>
<47B170BF.5000206@ptt.uni-due.de>
On Feb 12, 2008 4:11 AM, Thomas Zaksek <zaksek@ptt.uni-due.de> wrote:
> I tried turning off nestloop, but with terrible results:
Yeah, it didn't help. I was expecting the query planner to switch to
a more efficient join plan.
> I also tried to increase work_men, now the config is
> work_mem = 4MB
Try setting it higher for JUST THIS query. i.e.
set work_mem=128M;
explain analyze select ....
and see how that runs. Then play with it til you've got it down to
what helps. Note that work_mem in postgresql.conf being too large can
be dangerous, so it might be something you set for just this query for
safety reasons.
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To: pgsql-performance@postgresql.org
Cc: scott.marlowe@gmail.com, zaksek@ptt.uni-due.de
Subject: Re: Join Query Perfomance Issue
In-Reply-To: <dcc563d10802131336s366d66c6kcb9f1fd23818552b@mail.gmail.com>
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