Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 6E3C86503FF for ; Tue, 2 Sep 2008 15:33:36 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 50071-01-10 for ; Tue, 2 Sep 2008 15:33:15 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sd-2317.dedibox.fr (sd-2317.dedibox.fr [88.191.17.192]) by postgresql.org (Postfix) with ESMTP id 466B5650304 for ; Tue, 2 Sep 2008 14:06:39 -0300 (ADT) Received: from [192.168.10.64] (ASte-Genev-Bois-153-1-80-122.w86-203.abo.wanadoo.fr [86.203.226.122]) by sd-2317.dedibox.fr (Postfix) with ESMTP id 245902841; Tue, 2 Sep 2008 19:06:37 +0200 (CEST) Message-ID: <48BD7299.6010605@lelarge.info> Date: Tue, 02 Sep 2008 19:06:33 +0200 From: Guillaume Lelarge User-Agent: Thunderbird 2.0.0.16 (X11/20080724) MIME-Version: 1.0 To: Greg Smith CC: Duan Ligong , Alvaro Herrera , pgsql-performance@postgresql.org Subject: Re: too many clog files References: <20080901191255.E398.DUANLG@nec-as.nec.com.cn> <20080901143359.GC3776@alvh.no-ip.org> <20080902091602.CA09.DUANLG@nec-as.nec.com.cn> 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 tagged_above=0 required=5 tests=none X-Spam-Level: X-Archive-Number: 200809/37 X-Sequence-Number: 31350 Greg Smith a écrit : > [...] >> - When, or in what case is a new clog file produced? > > Every 32K transactions. Are you sure about this? y clog files get up to 262144 bytes. Which means 1000000 transactions' status: 262144 bytes are 2Mb (mega bits), so if a status is 2 bits, it holds 1M transactions' status). AFAICT, 32K transactions' status are available on a single (8KB) page. Or am I wrong? -- Guillaume. http://www.postgresqlfr.org http://dalibo.com