Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 165DD1336FA7 for ; Mon, 2 May 2011 01:08:31 -0300 (ADT) 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 36434-09 for ; Mon, 2 May 2011 04:08:09 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.186]) by mail.postgresql.org (Postfix) with ESMTP id D9B9A13364DE for ; Mon, 2 May 2011 01:08:08 -0300 (ADT) Received: from [192.168.1.6] (mail.highperformancepostgresql.com [71.179.240.8]) by mrelayeu.kundenserver.de (node=mrbap4) with ESMTP (Nemesis) id 0LpNZt-1PcTfG1RHJ-00fBiX; Mon, 02 May 2011 06:08:08 +0200 Message-ID: <4DBE2E80.50008@2ndQuadrant.com> Date: Mon, 02 May 2011 00:09:36 -0400 From: Greg Smith User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.16) Gecko/20110307 Icedove/3.0.11 MIME-Version: 1.0 To: pgsql-admin@postgresql.org Subject: Re: archive_timeout behavior (8.4.6) References: <4DB21BFA.4030800@consistentstate.com> In-Reply-To: <4DB21BFA.4030800@consistentstate.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Provags-ID: V02:K0:uDkYBbc8X1nplOngnHKPE7dxY8pUJmKJPmE59iMwt5S PtHNeLZ/wdm+MlFQbAi/VDbJlxJeQFTlAamUNEP6l2wwkUgSMm rx15u9QKj187bjxYlSRplcUn3wIvZ3gfAWmaG8yE1C8tl1kZZt oHzGwBn6DjnG4tVlB+JUV3AMAJW7n5resxHBloKYQapWr3xEjN fljVPADA1/KORIsTDlZ4h2FF4I6NgBFz36CzY9i0jw= 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, RCVD_IN_DNSWL_NONE=-0.0001 X-Spam-Level: X-Archive-Number: 201105/5 X-Sequence-Number: 37442 On 04/22/2011 08:23 PM, Brian Fehrle wrote: > So long story short, if a cluster has zero activity, and > archive_timeout is not set to 0, when it reaches that timeout should > it generate a file, or just skip because it would be 100% empty? You're right about what you've seen here, there is some logic in the WAL/checkpoint code that can avoid doing anything when the timeout hits, if there hasn't been any new WAL written since the last one. That hasn't changed for a while now though (since I've been watching that part of the source code at least) so I'm not sure what differences between 8.4.6 and earlier 8.4 versions you think you've observed. -- Greg Smith 2ndQuadrant US greg@2ndQuadrant.com Baltimore, MD PostgreSQL Training, Services, and 24x7 Support www.2ndQuadrant.us "PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books