Received: from localhost (maia-3.hub.org [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id 08C6C9FB314 for ; Sun, 28 Jan 2007 16:26:27 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-new, port 10024) with ESMTP id 81963-10 for ; Sun, 28 Jan 2007 16:26:21 -0400 (AST) 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 9ABC79FB1B8 for ; Sun, 28 Jan 2007 16:26:23 -0400 (AST) Received: by nf-out-0910.google.com with SMTP id x4so1841973nfb for ; Sun, 28 Jan 2007 12:26:22 -0800 (PST) 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=QVX5pBwMNRwsVtyioDaD7XFRgCwwJvutwpAlchxqSkuYugR+a6VojRD3NBsu6XopJKQNMSj6Q86haTJnsJZAHqxh8tqb/tPs5v14kXBVPF0NBNJSxCHpuQlgx7kqaez3dL1Lrlceeo0BAXLRrJpYxRPZ7+KF6Hh9/42VsNnNoY8= Received: by 10.82.152.16 with SMTP id z16mr3094870bud.1170015981657; Sun, 28 Jan 2007 12:26:21 -0800 (PST) Received: by 10.82.183.4 with HTTP; Sun, 28 Jan 2007 12:26:21 -0800 (PST) Message-ID: <1f30b80c0701281226k69f0d455qdd2a5b2dc85b80c5@mail.gmail.com> Date: Mon, 29 Jan 2007 01:26:21 +0500 From: imad To: "Campbell, Lance" Subject: Re: work-mem Cc: pgsql-performance@postgresql.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200701/395 X-Sequence-Number: 22996 work-mem tells the size of physical memory only, virtual memory is always there off course in case you run out of available memory. I recommend you reading PostgreSQL internals for all this stuff: http://www.postgresql.org/docs/8.0/static/internals.html --Imad www.EnterpriseDB.com On 1/29/07, Campbell, Lance wrote: > > > > > I have been researching how to improve my overall performance of postgres. > I am a little confused on the reasoning for how work-mem is used in the > postgresql.conf file. The way I understand the documentation is you define > with work-mem how much memory you want to allocate per search. Couldn't you > run out of memory? This approach seems kind of odd to me. How do you tell > the system not to allocate too much memory if you all of the sudden got hit > with a heavier number of queries? > > > > > > Thanks, > > > > Lance Campbell > > Project Manager/Software Architect > > Web Services at Public Affairs > > University of Illinois > > 217.333.0382 > > http://webservices.uiuc.edu > >