Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id ED1401337B49 for ; Tue, 16 Nov 2010 19:25:28 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 11091-02 for ; Tue, 16 Nov 2010 23:25:22 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from glacier.frostconsultingllc.com (glacier.frostconsultingllc.com [69.36.227.170]) by mail.postgresql.org (Postfix) with ESMTP id 77C711337B53 for ; Tue, 16 Nov 2010 19:25:21 -0400 (AST) Received: from dsl081-245-111.sfo1.dsl.speakeasy.net ([64.81.245.111] helo=Sidney-Stratton.local) by glacier.frostconsultingllc.com with esmtpsa (TLSv1:CAMELLIA256-SHA:256) (Exim 4.69) (envelope-from ) id 1PIUtq-0007lc-N3 for pgsql-performance@postgresql.org; Tue, 16 Nov 2010 15:25:21 -0800 Message-ID: <4CE312D9.6030503@agliodbs.com> Date: Tue, 16 Nov 2010 15:25:13 -0800 From: Josh Berkus User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1b3pre) Gecko/20090223 Thunderbird/3.0b2 MIME-Version: 1.0 To: pgsql-performance@postgresql.org Subject: Re: Defaulting wal_sync_method to fdatasync on Linux for 9.1? References: <4CCDCAA3.4050805@2ndquadrant.com> <201011010010.28724.andres@anarazel.de> <4CD472CC.80006@2ndquadrant.com> <4CE2EBF8.4040602@2ndquadrant.com> In-Reply-To: <4CE2EBF8.4040602@2ndquadrant.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-10 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201011/269 X-Sequence-Number: 41293 On 11/16/10 12:39 PM, Greg Smith wrote: > I want to next go through and replicate some of the actual database > level tests before giving a full opinion on whether this data proves > it's worth changing the wal_sync_method detection. So far I'm torn > between whether that's the right approach, or if we should just increase > the default value for wal_buffers to something more reasonable. We'd love to, but wal_buffers uses sysV shmem. -- -- Josh Berkus PostgreSQL Experts Inc. http://www.pgexperts.com