X-Original-To: pgsql-docs-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 41B9A9DC9BE for ; Tue, 17 Jan 2006 18:49:44 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 54797-03 for ; Tue, 17 Jan 2006 18:49:43 -0400 (AST) 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 3EC499DC9A4 for ; Tue, 17 Jan 2006 18:49:39 -0400 (AST) Received: by noel.decibel.org (Postfix, from userid 1001) id E45C039841; Tue, 17 Jan 2006 16:49:41 -0600 (CST) Date: Tue, 17 Jan 2006 16:49:41 -0600 From: "Jim C. Nasby" To: Scott Marlowe Cc: pgsql-docs@postgresql.org Subject: Re: vacuum and routine maintenance docs Message-ID: <20060117224941.GI17896@pervasive.com> References: <1137518049.25500.27.camel@state.g2switchworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1137518049.25500.27.camel@state.g2switchworks.com> X-Operating-System: FreeBSD 6.0-RELEASE amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.093 required=5 tests=[AWL=0.093] X-Spam-Score: 0.093 X-Spam-Level: X-Archive-Number: 200601/27 X-Sequence-Number: 3417 Before you 'put pen to paper', I have two articles that you should look at. One is on FSM, the other is more about MVCC from the standpoint of why we use it and why it means needing to vacuum. I don't have the URL's handy here, but I can post them tomorrow. On Tue, Jan 17, 2006 at 11:14:09AM -0600, Scott Marlowe wrote: > After the most recent post on the general mailing list by someone who > was a bit confused by postgresql's vacuuming and use of the free space > map, I've been reviewing the page on routine maintenance. > > It's pretty obvious that this page was originally written for an older > version of PostgreSQL and has had bits and pieces welded onto it over > time to cover newer features, like the autovacuum daemon. > > I'd like to rewrite most of the page, or at least the parts referring to > vacuuming and analyzing. They seem a bit scattered about on the page, > and there's no mention at all of the free space map, something which is > integral to vacuuming the database. > > So, before I go of slogging through the snow, a couple of questions. > > 1: Is there already a newer version in CVS? Should I check out the > docs/src directory from there to start? Or can I just go on what's in > the 8.1 release? > > 2: Any input on anyone as to what they feel they'd like to see in the > docs for this section? > > The section on vacuuming and analysis seem kind of light on theory. I'm > thinking we should mention something about the default statistics or at > least a reference to a page that explains it. > > This also leads me to believe that what we cover on the > runtime-config-resource page, because the coverage of the fsm there is > kind of light too. > > So, any advice? > > ---------------------------(end of broadcast)--------------------------- > TIP 9: In versions below 8.0, the planner will ignore your desire to > choose an index scan if your joining column's datatypes do not > match > -- 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