Received: from localhost (maia-2.hub.org [200.46.204.187]) by postgresql.org (Postfix) with ESMTP id C8A129FB811 for ; Tue, 19 Jun 2007 10:27:03 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.187]) (amavisd-maia, port 10024) with ESMTP id 84355-01 for ; Tue, 19 Jun 2007 10:26:49 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from lists.commandprompt.com (host-254.commandprompt.net [207.173.203.254]) by postgresql.org (Postfix) with ESMTP id 146109FB774 for ; Tue, 19 Jun 2007 10:26:54 -0300 (ADT) Received: from perhan.alvh.no-ip.org (190-13-143-52.bk13-dsl.surnet.cl [190.13.143.52]) (authenticated bits=0) by lists.commandprompt.com (8.13.7/8.13.6) with ESMTP id l5JDQlX6023654; Tue, 19 Jun 2007 06:26:52 -0700 Received: by perhan.alvh.no-ip.org (Postfix, from userid 1000) id A630732A23; Tue, 19 Jun 2007 09:26:43 -0400 (CLT) Date: Tue, 19 Jun 2007 09:26:43 -0400 From: Alvaro Herrera To: Karl Wright Cc: Tom Lane , pgsql-performance@postgresql.org Subject: Re: Performance query about large tables, lots of concurrent access Message-ID: <20070619132643.GC4265@alvh.no-ip.org> References: <4676DD57.7070304@metacarta.com> <14291.1182221811@sss.pgh.pa.us> <4677B831.8060704@metacarta.com> <4677D298.2010109@metacarta.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4677D298.2010109@metacarta.com> User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: ClamAV version 0.88.5, clamav-milter version 0.88.5 on projects.commandprompt.com X-Virus-Status: Clean X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (lists.commandprompt.com [192.168.2.159]); Tue, 19 Jun 2007 06:26:53 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200706/334 X-Sequence-Number: 25367 Karl Wright wrote: > This particular run lasted four days before a VACUUM became essential. > The symptom that indicates that VACUUM is needed seems to be that the > CPU usage of any given postgresql query skyrockets. Is this essentially > correct? Are you saying you weren't used to run VACUUM all the time? If so, that's where the problem lies. -- Alvaro Herrera http://www.amazon.com/gp/registry/CTMLCN8V17R4 "Cómo ponemos nuestros dedos en la arcilla del otro. Eso es la amistad; jugar al alfarero y ver qué formas se pueden sacar del otro" (C. Halloway en La Feria de las Tinieblas, R. Bradbury)