X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 50B999DC86A for ; Tue, 17 Jan 2006 06:19:02 -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 81418-07 for ; Tue, 17 Jan 2006 06:19:03 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from floppy.pyrenet.fr (floppy.pyrenet.fr [194.116.145.2]) by postgresql.org (Postfix) with ESMTP id 7D6629DC807 for ; Tue, 17 Jan 2006 06:18:59 -0400 (AST) Received: by floppy.pyrenet.fr (Postfix, from userid 106) id A395730949; Tue, 17 Jan 2006 11:19:01 +0100 (MET) From: Michael Riess X-Newsgroups: pgsql.performance Subject: Autovacuum / full vacuum Date: Tue, 17 Jan 2006 11:18:59 +0100 Organization: Hub.Org Networking Services Lines: 19 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@news.hub.org User-Agent: Thunderbird 1.5 (Windows/20051201) To: pgsql-performance@postgresql.org X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.04 required=5 tests=[AWL=0.040] X-Spam-Score: 0.04 X-Spam-Level: X-Archive-Number: 200601/218 X-Sequence-Number: 16696 hi, I'm curious as to why autovacuum is not designed to do full vacuum. I know that the necessity of doing full vacuums can be reduced by increasing the FSM, but in my opinion that is the wrong decision for many applications. My application does not continuously insert/update/delete tuples at a constant rate. Basically there are long periods of relatively few modifications and short burst of high activity. Increasing the FSM so that even during these bursts most space would be reused would mean to reduce the available memory for all other database tasks. So my question is: What's the use of an autovacuum daemon if I still have to use a cron job to do full vacuums? wouldn't it just be a minor job to enhance autovacuum to be able to perform full vacuums, if one really wants it to do that - even if some developers think that it's the wrong approach? Mike