X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 59F8052814 for ; Thu, 9 Jun 2005 10:15:30 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 79118-02 for ; Thu, 9 Jun 2005 13:15:21 +0000 (GMT) Received: from mail.metronet.co.uk (mail.metronet.co.uk [213.162.97.75]) by svr1.postgresql.org (Postfix) with ESMTP id 54831528A9 for ; Thu, 9 Jun 2005 10:15:19 -0300 (ADT) Received: from mainbox.archonet.com (84-51-143-99.archon037.adsl.metronet.co.uk [84.51.143.99]) by smtp.metronet.co.uk (MetroNet Mail) with ESMTP id D9F294146A4; Thu, 9 Jun 2005 14:15:13 +0100 (BST) Received: from localhost (localhost.localdomain [127.0.0.1]) by mainbox.archonet.com (Postfix) with ESMTP id A05D515ED7; Thu, 9 Jun 2005 14:11:25 +0100 (BST) Received: from mainbox.archonet.com ([127.0.0.1]) by localhost (mainbox [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 21794-05; Thu, 9 Jun 2005 14:11:23 +0100 (BST) Received: from [192.168.1.17] (client17.office.archonet.com [192.168.1.17]) by mainbox.archonet.com (Postfix) with ESMTP id 5D75915ED5; Thu, 9 Jun 2005 14:11:23 +0100 (BST) Message-ID: <42A83FFA.3030209@archonet.com> Date: Thu, 09 Jun 2005 14:11:22 +0100 From: Richard Huxton User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050317) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Yann Michel Cc: pgsql-performance@postgresql.org Subject: Re: postgresql.conf runtime statistics default References: <20050609100852.GA16538@zoom.spline.inf.fu-berlin.de> In-Reply-To: <20050609100852.GA16538@zoom.spline.inf.fu-berlin.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.054 tagged_above=0 required=5 tests=AWL, FORGED_RCVD_HELO X-Spam-Level: X-Archive-Number: 200506/210 X-Sequence-Number: 12847 Yann Michel wrote: > > To my question: I found the parameter "stats_reset_on_server_start" > which is set to true by default. Why did you choose this (and not false) > and what are the impacts of changeing it to false? I mean, as long as I > understood it, each query or statements generates some statistic data > which is used by the optimizer (or anything equal) later on. So in my > oppinion, wouldn't it be better so set this parameter to false and to > enable a kind of a "startup reset_stats" option? This is administrator statistics (e.g. number of disk blocks read from this index) not planner statistics. You're right - it would be foolish to throw away planner stats. -- Richard Huxton Archonet Ltd