X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id 0AA5B11F6223 for ; Mon, 24 Apr 2006 15:14:56 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 53145-02-3 for ; Mon, 24 Apr 2006 15:14:31 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id 6EAFD11F657F for ; Mon, 24 Apr 2006 14:09:38 -0300 (ADT) Received: by noel.decibel.org (Postfix, from userid 1001) id AC27156427; Mon, 24 Apr 2006 12:09:15 -0500 (CDT) Received: (hashcash-sendmail, from uid 1001); Mon, 24 Apr 2006 12:09:15 -0500 Date: Mon, 24 Apr 2006 12:09:15 -0500 From: "Jim C. Nasby" To: Will Reese Cc: pgsql-performance@postgresql.org Subject: Re: Slow deletes in 8.1 when FKs are involved Message-ID: <20060424170914.GE38186@pervasive.com> References: <22780344-3C6A-474E-8101-60B8806DA152@rackspace.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <22780344-3C6A-474E-8101-60B8806DA152@rackspace.com> X-Operating-System: FreeBSD 6.0-RELEASE-p4 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Hashcash: 1:20:060424:wreese@rackspace.com::EhiWj6Hj9TOR7AxI:00000000000000000 0000000000000000000000002Avn X-Hashcash: 1:20:060424:pgsql-performance@postgresql.org::lLMiIGXFuJ++sjbt:00000 00000000000000000000000037fm X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200604/524 X-Sequence-Number: 18608 On Sun, Apr 23, 2006 at 09:41:14PM -0500, Will Reese wrote: > I'm preparing for an upgrade from PostgreSQL 7.4.5 to 8.1.3, and I > noticed a potential performance issue. > > I have two servers, a dual proc Dell with raid 5 running PostgreSQL > 7.4, and a quad proc Dell with a storage array running PostgreSQL > 8.1. Both servers have identical postgresql.conf settings and were BTW, you'll want to tweak some things between the two .conf files, especially if the 8.1.3 server has more memory. Faster drive array means you probably want to tweak random_page_cost down. Also, 8.1.3 has a lot of new config settings compared to 7.4.x; it'd probably be best to take the default 8.1 config and tweak it, rather than bringing the 7.4 config over. -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461