From: Steinar H. Gunderson <sgunderson@bigfoot.com>
To: Liviu Ionescu <ilgb@livius.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: performance drop on 8.2.4, reverting to 8.1.4
Date: Fri, 18 May 2007 11:49:21 +0200
Message-ID: <20070518094921.GA13598@uio.no> (raw)
In-Reply-To: <006501c7992b$4d29ffb0$653e10ac@ilgvaio>
References: <006501c7992b$4d29ffb0$653e10ac@ilgvaio>
On Fri, May 18, 2007 at 12:02:44PM +0300, Liviu Ionescu wrote:
> the 8.2.4 plan with join_collapse_limit = 1 (with default it was worse, full of nested loops)
It will probably be useful with EXPLAIN ANALYZE of your queries, not just the
EXPLAIN.
> "Nested Loop Left Join (cost=32.01..2012.31 rows=1 width=230)"
It looks like the planner thinks this is going to be really cheap -- so it's
misestimating something somewhere. Have you ANALYZEd recently?
/* Steinar */
--
Homepage: http://www.sesse.net/
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To: pgsql-performance@postgresql.org
Cc: sgunderson@bigfoot.com, ilgb@livius.net
Subject: Re: performance drop on 8.2.4, reverting to 8.1.4
In-Reply-To: <20070518094921.GA13598@uio.no>
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