Received: from maia.hub.org (unknown [200.46.208.211]) by mail.postgresql.org (Postfix) with ESMTP id D7357634031 for ; Sat, 3 Apr 2010 08:58:48 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.208.211]) (amavisd-maia, port 10024) with ESMTP id 26030-06 for ; Sat, 3 Apr 2010 11:58:31 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sd-17937.dedibox.fr (sd-17937.dedibox.fr [88.191.100.74]) by mail.postgresql.org (Postfix) with ESMTP id 4855B633E0E for ; Sat, 3 Apr 2010 08:58:38 -0300 (ADT) Received: from [192.168.10.3] (ASte-Genev-Bois-153-1-79-201.w86-203.abo.wanadoo.fr [86.203.225.201]) by sd-17937.dedibox.fr (Postfix) with ESMTPA id 274C63B8F5; Sat, 3 Apr 2010 13:58:36 +0200 (CEST) Message-ID: <4BB72D6B.7080009@lelarge.info> Date: Sat, 03 Apr 2010 13:58:35 +0200 From: Guillaume Lelarge User-Agent: Mozilla/5.0 (X11; U; Linux i686; fr; rv:1.9.1.9) Gecko/20100317 Thunderbird/3.0.4 MIME-Version: 1.0 To: "Campbell, Lance" CC: Greg Smith , pgsql-performance@postgresql.org Subject: Re: How much memory is PostgreSQL using References: <4BB0DB0D.80208@2ndquadrant.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-0.691 tagged_above=-10 required=5 tests=AWL=-0.692, BAYES_50=0.001 X-Spam-Level: X-Archive-Number: 201004/26 X-Sequence-Number: 38276 Le 02/04/2010 22:10, Campbell, Lance a écrit : > Greg, > Thanks for your help. > > 1) How does the number of buffers provided by pg_buffercache compare to > memory (buffers * X = Y meg)? 1 buffer is 8 KB. > 2) Is there a way to tell how many total buffers I have available/max? With pg_buffercache, yes. SELECT count(*) FROM pg_buffercache WHERE relfilenode IS NOT NULL; should give you the number of non-empty buffers. -- Guillaume. http://www.postgresqlfr.org http://dalibo.com