Received: from localhost (maia-5.hub.org [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id 48EF99FC1BC for ; Fri, 25 May 2007 17:05:30 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-maia, port 10024) with ESMTP id 43120-01 for ; Fri, 25 May 2007 17:05:23 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from cassarossa.samfundet.no (cassarossa.samfundet.no [129.241.93.19]) by postgresql.org (Postfix) with ESMTP id 2CE2E9FB8AC for ; Fri, 25 May 2007 17:05:25 -0300 (ADT) Received: from trofast.ipv6.sesse.net ([2001:700:300:1803:20e:cff:fe36:a766] helo=trofast.sesse.net) by cassarossa.samfundet.no with esmtp (Exim 4.50) id 1Hrg2N-0000eg-Lh for pgsql-performance@postgresql.org; Fri, 25 May 2007 22:05:23 +0200 Received: from sesse by trofast.sesse.net with local (Exim 3.36 #1 (Debian)) id 1Hrg2N-00043N-00 for ; Fri, 25 May 2007 22:05:23 +0200 Date: Fri, 25 May 2007 22:05:23 +0200 From: "Steinar H. Gunderson" To: pgsql-performance@postgresql.org Subject: Re: Performance problem on 8.2.4, but not 8.2.3 Message-ID: <20070525200523.GA15547@uio.no> Mail-Followup-To: pgsql-performance@postgresql.org References: <2C91A79B-6AFD-4734-B245-2ED81F4F15D4@mediamatters.org> <21071.1180122995@sss.pgh.pa.us> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <21071.1180122995@sss.pgh.pa.us> X-Operating-System: Linux 2.6.20.4 on a x86_64 X-Message-Flag: Outlook? --> http://www.mozilla.org/products/thunderbird/ User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200705/538 X-Sequence-Number: 24928 On Fri, May 25, 2007 at 03:56:35PM -0400, Tom Lane wrote: > I looked through the CVS logs and didn't find any planner changes > between 8.2.3 and 8.2.4 that seem likely to affect your query, so > I'm thinking it must be a statistical discrepancy. It looks like the estimated cost is lower for 8.2.4 -- could it be that the fact that he's giving it more memory lead to the planner picking a plan that happens to be worse? /* Steinar */ -- Homepage: http://www.sesse.net/