Received: from localhost (maia-5.hub.org [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id C32B09FBE95 for ; Wed, 20 Jun 2007 14:53:12 -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 94365-03 for ; Wed, 20 Jun 2007 14:53:06 -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 DD47F9FB43C for ; Wed, 20 Jun 2007 14:53:07 -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 l5KHr2se011084; Wed, 20 Jun 2007 10:53:07 -0700 Received: by perhan.alvh.no-ip.org (Postfix, from userid 1000) id 342FF32A2C; Wed, 20 Jun 2007 13:53:00 -0400 (CLT) Date: Wed, 20 Jun 2007 13:53:00 -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: <20070620175300.GN30369@alvh.no-ip.org> References: <4676DD57.7070304@metacarta.com> <14291.1182221811@sss.pgh.pa.us> <4677B831.8060704@metacarta.com> <4677D298.2010109@metacarta.com> <20070619132643.GC4265@alvh.no-ip.org> <4677DC06.3000300@metacarta.com> <20070619134637.GG4265@alvh.no-ip.org> <467963A8.2060703@metacarta.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <467963A8.2060703@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 10:53:07 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200706/432 X-Sequence-Number: 25465 Karl Wright wrote: > (b) the performance of individual queries had already degraded > significantly in the same manner as what I'd seen before. You didn't answer whether you had smaller, more frequently updated tables that need more vacuuming. This comment makes me think you do. I think what you should be looking at is whether you can forget vacuuming the whole database in one go, and make it more granular. -- Alvaro Herrera http://www.flickr.com/photos/alvherre/ "Having your biases confirmed independently is how scientific progress is made, and hence made our great society what it is today" (Mary Gardiner)