Received: from localhost (maia-1.hub.org [200.46.204.191]) by postgresql.org (Postfix) with ESMTP id C08099FBFB3 for ; Thu, 24 May 2007 23:57:01 -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 41357-10 for ; Thu, 24 May 2007 23:56:53 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from lists.commandprompt.com (host-254.commandprompt.net [207.173.203.254]) by postgresql.org (Postfix) with ESMTP id BF8A99FBD21 for ; Thu, 24 May 2007 23:56:53 -0300 (ADT) Received: from [192.168.1.50] (or-67-76-146-141.sta.embarqhsd.net [67.76.146.141]) (authenticated bits=0) by lists.commandprompt.com (8.13.7/8.13.6) with ESMTP id l4P2uWjU023566; Thu, 24 May 2007 19:56:35 -0700 Message-ID: <46565086.2040705@commandprompt.com> Date: Thu, 24 May 2007 19:57:10 -0700 From: "Joshua D. Drake" User-Agent: Thunderbird 1.5.0.10 (X11/20070403) MIME-Version: 1.0 To: Tom Lane CC: Alvaro Herrera , George Pavlov , pgsql-general@postgresql.org Subject: Re: index vs. seq scan choice? References: <8C5B026B51B6854CBE88121DBF097A86C3A30D@ehost010-33.exch010.intermedia.net> <27828.1180055291@sss.pgh.pa.us> <20070525023922.GV4320@alvh.no-ip.org> <29662.1180061117@sss.pgh.pa.us> In-Reply-To: <29662.1180061117@sss.pgh.pa.us> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit 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]); Thu, 24 May 2007 19:56:35 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200705/1235 X-Sequence-Number: 114429 Tom Lane wrote: > Alvaro Herrera writes: >> Tom Lane wrote: >>> (The default statistics target is 10, which is widely considered too >>> low --- you might find 100 more suitable.) > >> Does this mean that we should look into raising the default a bit? > > Probably ... the question is to what. > > The default of 10 was chosen in our usual spirit of conservatism --- > and IIRC it was replacing code that tracked only *one* most common > value, so it was already a factor of 10 better (and more expensive) > than what was there before. But subsequent history suggests it's > too small. I'm not sure I want to vote for another 10x increase by > default, though. Outside of longer analyze times, and slightly more space taken up by the statistics, what is the downside? I mean in reality... what is setting to 100 going to do to effect actual production usage of even a modest machine? Sincerely, Joshua D. Drake > > regards, tom lane > > ---------------------------(end of broadcast)--------------------------- > TIP 1: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly > -- === The PostgreSQL Company: Command Prompt, Inc. === Sales/Support: +1.503.667.4564 || 24x7/Emergency: +1.800.492.2240 Providing the most comprehensive PostgreSQL solutions since 1997 http://www.commandprompt.com/ Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate PostgreSQL Replication: http://www.commandprompt.com/products/