Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 8ECF51337B5E for ; Fri, 7 Jan 2011 09:39:42 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 76583-01 for ; Fri, 7 Jan 2011 13:39:35 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.anarazel.de (mail.anarazel.de [217.115.131.40]) by mail.postgresql.org (Postfix) with ESMTP id C1E9F13364DE for ; Fri, 7 Jan 2011 09:39:34 -0400 (AST) Received: from alap2.localnet (p579FBE52.dip.t-dialin.net [87.159.190.82]) by mail.anarazel.de (Postfix) with ESMTPSA id B9D4B448004; Fri, 7 Jan 2011 14:39:33 +0100 (CET) From: Andres Freund To: pgsql-performance@postgresql.org Subject: Re: Wrong docs on checkpoint_segments? Date: Fri, 7 Jan 2011 14:39:31 +0100 User-Agent: KMail/1.13.5 (Linux/2.6.37-rc6-andres-00186-ge5fcdb7; KDE/4.5.90; x86_64; ; ) Cc: Florian Weimer References: <82aajcg9wa.fsf@mid.bfk.de> In-Reply-To: <82aajcg9wa.fsf@mid.bfk.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201101071439.32053.andres@anarazel.de> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.91 tagged_above=-10 required=5 tests=BAYES_00=-1.9, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201101/42 X-Sequence-Number: 41829 On Friday, January 07, 2011 01:45:25 PM Florian Weimer wrote: > On 9.0, this configuration > > checkpoint_segments = 512 # in logfile segments, min 1, 16MB each > > results in 1034 segments, so the effective logfile segment size is 32 MB. Um. Is it possible that you redefined XLOG_SEG_SIZE or used --with-wal- segsize=SEGSIZE? The default is still: andres@alap2:~/src/postgresql$ grep XLOG_SEG_SIZE src/include/pg_config.h /* XLOG_SEG_SIZE is the size of a single WAL file. This must be a power of 2 XLOG_BLCKSZ). Changing XLOG_SEG_SIZE requires an initdb. */ #define XLOG_SEG_SIZE (16 * 1024 * 1024) Andres