Received: from localhost (maia-3.hub.org [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id C926D9FBB15 for ; Tue, 29 May 2007 14:56:15 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 79567-09 for ; Tue, 29 May 2007 14:56:08 -0300 (ADT) X-Greylist: delayed 00:52:23.719011 by SQLgrey-1.7.5 Received: from obelix.askesis.nl (laudanum.demon.nl [82.161.125.16]) by postgresql.org (Postfix) with ESMTP id 43B489FB987 for ; Tue, 29 May 2007 14:56:11 -0300 (ADT) Received: obelix 172.31.0.1 from 172.31.1.1 172.31.1.1 via HTTP with MS-WebStorage 6.0.6249 Received: from panoramix by obelix; 29 May 2007 19:56:08 +0200 Subject: Re: Vacuum takes forever From: Joost Kraaijeveld To: PFC Cc: postgresql performance list In-Reply-To: References: <1180458223.18930.16.camel@panoramix> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Tue, 29 May 2007 19:56:07 +0200 Message-Id: <1180461367.18930.25.camel@panoramix> Mime-Version: 1.0 X-Mailer: Evolution 2.6.3 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.169 tagged_above=0 required=5 tests=AWL=0.032, BAYES_50=0.001, FORGED_RCVD_HELO=0.135, UNPARSEABLE_RELAY=0.001 X-Spam-Level: X-Archive-Number: 200705/585 X-Sequence-Number: 24975 On Tue, 2007-05-29 at 19:16 +0200, PFC wrote: > > > Could this be because of my Cost-Based Vacuum Delay settings ? > > Yeah. It is supposed to slow down VACUUM so it doesn't kill your server, > but it is not aware of the load. It will also slow it down if there is no > load. That is its purpose after all ;) > If you want fast vacuum, issue SET vacuum_cost_delay = 0; before. Thanks, I tried it and it worked. I did not know that changing this setting would result in such a performance drop ( I just followed an advise I read on http://www.powerpostgresql.com/PerfList/) which mentioned a tripling of the the execution time. Not a change from 8201819 ms to 17729 ms. -- Groeten, Joost Kraaijeveld Askesis B.V. Molukkenstraat 14 6524NB Nijmegen tel: 024-3888063 / 06-51855277 fax: 024-3608416 web: www.askesis.nl