Received: from localhost (maia-5.hub.org [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id D14279FB487 for ; Sun, 18 Mar 2007 10:18:25 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-new, port 10024) with ESMTP id 70100-04 for ; Sun, 18 Mar 2007 10:18:17 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.4 Received: from nf-out-0910.google.com (nf-out-0910.google.com [64.233.182.190]) by postgresql.org (Postfix) with ESMTP id 7EE479FB478 for ; Sun, 18 Mar 2007 10:18:22 -0300 (ADT) Received: by nf-out-0910.google.com with SMTP id x4so777412nfb for ; Sun, 18 Mar 2007 06:18:20 -0700 (PDT) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=hyCal68QbHxE5msDP/zmPllr2d1ZliRX0QyZUVwdacW2sW/C8bMG7tunn3McMTwGkKwoUn61cFdmFRxWc92yuYP2e40CSU9K/6NdfkyT+82UKdyXaVvgE+wka1LpoJLRo4L9G0gc0e+W3gEa4F9Ieq2CPP10nj41dBprSznO/3M= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=dhAvajtxolj9E25OBEKzSjmAsfAjldYXhxznW7J2Kx/KObb7OJazIrsQb7szY97gFDjPLSUc+09XuW/Pr2fJ6g+F5gpSWCVz4e6TazpfI5JZoYC9rIljny5ESBB9bRH6I6GKwGbeeT/LE9SFZ52f/p1NXr+diWzSb32kuXAbZi4= Received: by 10.65.228.5 with SMTP id f5mr5509613qbr.1174223899788; Sun, 18 Mar 2007 06:18:19 -0700 (PDT) Received: by 10.140.13.3 with HTTP; Sun, 18 Mar 2007 06:18:19 -0700 (PDT) Message-ID: <9e4684ce0703180618m33fe9ec4v3007a673d28df591@mail.gmail.com> Date: Sun, 18 Mar 2007 14:18:19 +0100 From: "hubert depesz lubaczewski" To: "Barry Moore" Subject: Re: Performance Tuning and Disk Cache Cc: pgsql-performance@postgresql.org In-Reply-To: <1862C4AD-EB83-4D58-B1F2-45BDC47E5608@genetics.utah.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1862C4AD-EB83-4D58-B1F2-45BDC47E5608@genetics.utah.edu> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200703/268 X-Sequence-Number: 23673 On 3/18/07, Barry Moore wrote: > Does anyone know how I can repeatedly run the same query in the > "worst case scenario" of no postgres data in the disk cache (e.g., > clear the page cache or force it to be ignored)? try to disconnect from postgresql, reconnect, rerun the query. if it doesn't help - you can try unmounting filesystem which contains postgresql data, and remounting it again. of course with postgresql shutdown. depesz -- http://www.depesz.com/ - nowy, lepszy depesz