Received: from localhost (maia-1.hub.org [200.46.204.191]) by postgresql.org (Postfix) with ESMTP id 17A239FB344 for ; Wed, 20 Jun 2007 15:06:39 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.191]) (amavisd-maia, port 10024) with ESMTP id 95860-05 for ; Wed, 20 Jun 2007 15:06:35 -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 8918B9FB291 for ; Wed, 20 Jun 2007 15:06:32 -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 l5KI6Un2011513; Wed, 20 Jun 2007 11:06:31 -0700 Received: by perhan.alvh.no-ip.org (Postfix, from userid 1000) id 4E73332A2C; Wed, 20 Jun 2007 14:06:28 -0400 (CLT) Date: Wed, 20 Jun 2007 14:06:28 -0400 From: Alvaro Herrera To: Karl Wright Cc: Francisco Reyes , Tom Lane , pgsql-performance@postgresql.org Subject: Re: Performance query about large tables, lots of concurrent access Message-ID: <20070620180628.GQ30369@alvh.no-ip.org> References: <4677D298.2010109@metacarta.com> <20070619132643.GC4265@alvh.no-ip.org> <4677DC06.3000300@metacarta.com> <20070619134637.GG4265@alvh.no-ip.org> <467963A8.2060703@metacarta.com> <20070620175300.GN30369@alvh.no-ip.org> <46796A08.8080601@metacarta.com> <20070620175758.GP30369@alvh.no-ip.org> <46796BF0.8010302@metacarta.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <46796BF0.8010302@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]); Wed, 20 Jun 2007 11:06:32 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200706/439 X-Sequence-Number: 25472 Karl Wright wrote: > Alvaro Herrera wrote: > >Karl Wright wrote: > >>I am afraid that I did answer this. My largest tables are the ones > >>continually being updated. The smaller ones are updated only > >>infrequently. > > > >Can you afford to vacuum them in parallel? > > Hmm, interesting question. If VACUUM is disk limited then it wouldn't > help, probably, unless I moved various tables to different disks > somehow. Let me think about whether that might be possible. Well, is it disk limited? Do you have the vacuum_delay stuff enabled? -- Alvaro Herrera http://www.flickr.com/photos/alvherre/ "I would rather have GNU than GNOT." (ccchips, lwn.net/Articles/37595/)