Subject: Re: Extremely irregular query performance
From: Mark Lewis <mark.lewis@mir3.com>
To: Jean-Philippe =?ISO-8859-1?Q?C=F4t=E9?=
	<jean-philippe.cote@crt.umontreal.ca>
Cc: pgsql-performance@postgresql.org
In-Reply-To: <20060111234149.05DEA384099@crt0.crt.umontreal.ca>
References: <20060111234149.05DEA384099@crt0.crt.umontreal.ca>
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Organization: MIR3, Inc.
Date: Wed, 11 Jan 2006 15:50:43 -0800
Message-Id: <1137023443.30926.2.camel@archimedes>
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If this is a query that will be executed more than once, you can also
avoid incurring the planning overhead multiple times by using PREPARE.

-- Mark Lewis

On Wed, 2006-01-11 at 18:50 -0500, Jean-Philippe C=C3=B4t=C3=A9 wrote:
> Thanks a lot for this info, I was indeed exceeding the genetic
> optimizer's threshold.  Now that it is turned off, I get
> a very stable response time of 435ms (more or less 5ms) for
> the same query. It is about three times slower than the best
> I got with the genetic optimizer on, but the overall average
> is much lower.
>=20
> I'll also try to play with the geqo parameters and see if things
> improve.
>=20
> Thanks again,
>=20
> J-P