Received: from localhost (maia-2.hub.org [200.46.204.187]) by postgresql.org (Postfix) with ESMTP id 1D95D9FBEBA for ; Thu, 9 Aug 2007 10:14:57 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.187]) (amavisd-maia, port 10024) with ESMTP id 55142-10 for ; Thu, 9 Aug 2007 10:13:55 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from vms042pub.verizon.net (vms042pub.verizon.net [206.46.252.42]) by postgresql.org (Postfix) with ESMTP id 72CE79FBEC9 for ; Thu, 9 Aug 2007 10:14:00 -0300 (ADT) Received: from osgiliath.mathom.us ([72.66.31.72]) by vms042.mailsrvcs.net (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPA id <0JMI00J0HCQZYBJ8@vms042.mailsrvcs.net> for pgsql-performance@postgresql.org; Thu, 09 Aug 2007 08:13:47 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 2319D1F82E for ; Thu, 09 Aug 2007 09:13:46 -0400 (EDT) Received: from osgiliath.mathom.us ([127.0.0.1]) by localhost (osgiliath.home.mathom.us [127.0.0.1]) (amavisd-new, port 10024) with LMTP id zU-ISzmJzVtf for ; Thu, 09 Aug 2007 09:13:45 -0400 (EDT) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id C19C91F816; Thu, 09 Aug 2007 09:13:44 -0400 (EDT) Date: Thu, 09 Aug 2007 09:13:44 -0400 From: Michael Stone Subject: Re: Update table performance In-reply-to: To: pgsql-performance@postgresql.org Mail-followup-to: pgsql-performance@postgresql.org Message-id: <20070809131342.GK22785@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Virus-Scanned: Debian amavisd-new at mathom.us X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 References: <20070807214227.GR25704@nasby.net> <670773.87500.qm@web32209.mail.mud.yahoo.com> User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200708/82 X-Sequence-Number: 26212 On Thu, Aug 09, 2007 at 06:04:09PM +0530, Merlin Moncure wrote: >keep an eye for the HOT feature which will hopefully make 8.3 that >will highly reduce the penalty for (small) updates in many cases. Is there an overview somewhere about how this feature works and what it is expected to do? There have been a lot of references to it over time, and it's possible to understand it if you follow list traffic over time, but starting cold it's hard to know what it is. The name was poorly chosen as far as google is concerned. :) Mike Stone