Received: from maia.hub.org (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id 3056D632FB3 for ; Thu, 18 Mar 2010 06:02:56 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 49249-10 for ; Thu, 18 Mar 2010 09:02:45 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from outmail137193.authsmtp.co.uk (outmail137193.authsmtp.co.uk [62.13.137.193]) by mail.postgresql.org (Postfix) with ESMTP id 9D96F63272C for ; Thu, 18 Mar 2010 06:02:45 -0300 (ADT) Received: from mail-c194.authsmtp.com (mail-c194.authsmtp.com [62.13.128.121]) by punt7.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id o2I92SEL058388; Thu, 18 Mar 2010 09:02:28 GMT Received: from [192.168.0.4] (88-110-151-22.dynamic.dsl.as9105.com [88.110.151.22]) (authenticated bits=0) by mail.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id o2I92Njs011191; Thu, 18 Mar 2010 09:02:23 GMT Subject: Re: Autovac vs manual with analyze From: Simon Riggs To: Scott Whitney Cc: pgsql-admin@postgresql.org In-Reply-To: <18735708.169861268677235843.JavaMail.root@zimbra.int.journyx.com> References: <18735708.169861268677235843.JavaMail.root@zimbra.int.journyx.com> Content-Type: text/plain Date: Thu, 18 Mar 2010 09:02:22 +0000 Message-Id: <1268902942.3827.1696.camel@ebony> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit X-Server-Quench: f7a32745-326c-11df-80b9-0022640b883e X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCdxZQATClZOTQEd DAteCiN5VAwpPBRK HVkIKg5MJUcNSQVJ NksadBtFaQ1bYFhD HGQLWlREUFR7WWF/ aQkfZQ1DY0tOQQRv UVZLQE1XHAJ3AVJe BGcXUGcoNAVHeX95 ZAhjV3hZEhJ9JEV/ RUpRCG4EYzR9aWFL Bl1Qd1FdbQNKfB1D blAtXHsONCtlM3Bw LCYfGhEXCH12NThS XAgGZUwJCUMCGCM1 Q1gdHCkvVUQDTiEi PRFO X-Authentic-SMTP: 61633235383639.1015:706/Kp X-AuthFastPath: 255 X-Virus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-2.599 tagged_above=-10 required=5 tests=BAYES_00=-2.599 X-Spam-Level: X-Archive-Number: 201003/119 X-Sequence-Number: 33918 On Mon, 2010-03-15 at 13:20 -0500, Scott Whitney wrote: > My problem is that each Saturday at midnight, I have to start a > vacuumdb -f -z -a or my pg_clog dir never clears out. Why is your pg_clog dir a problem? > So, my questions are: > > a) Is the manual vacuum needed for performance reasons, or is auto-vac > sufficient? If you don't know why you are running it, then you should skip it and measure the difference. -- Simon Riggs www.2ndQuadrant.com