Received: from localhost (unknown [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id F181D2E0191 for ; Wed, 13 Feb 2008 19:05:36 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 99536-01 for ; Wed, 13 Feb 2008 19:05:27 -0400 (AST) Received: from davinci.ethosmedia.com (server227.ethosmedia.com [209.128.84.227]) by postgresql.org (Postfix) with ESMTP id 85F502E014E for ; Wed, 13 Feb 2008 19:04:50 -0400 (AST) X-EthosMedia-Virus-Scanned: no infections found Received: from [64.81.245.111] (account josh@agliodbs.com HELO [192.168.1.27]) by davinci.ethosmedia.com (CommuniGate Pro SMTP 4.1.8) with ESMTP-TLS id 15310378; Wed, 13 Feb 2008 15:08:51 -0800 From: Josh Berkus Reply-To: josh@agliodbs.com Organization: Aglio Database Solutions To: Tom Lane Subject: Re: HOT TOAST? Date: Wed, 13 Feb 2008 15:07:13 -0800 User-Agent: KMail/1.8 Cc: pgsql-performance@postgresql.org References: <200802130950.15431.josh@agliodbs.com> <20169.1202925879@sss.pgh.pa.us> In-Reply-To: <20169.1202925879@sss.pgh.pa.us> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200802131507.13659.josh@agliodbs.com> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200802/154 X-Sequence-Number: 28696 Tom, > The current TOAST code never does any updates, only inserts/deletes. > But the HOT logic should be able to reclaim deleted rows early via > pruning. OK, so for a heavy update application we should still see a vacuum reduction, even if most of the rows are 40k large? Time to run some tests ... -- --Josh Josh Berkus PostgreSQL @ Sun San Francisco