X-Original-To: pgsql-sql@postgresql.org Received: from localhost (unknown [64.117.224.193]) by developer.postgresql.org (Postfix) with ESMTP id 77CF3925495 for ; Mon, 19 May 2003 19:29:44 -0400 (EDT) Received: from developer.postgresql.org ([64.117.224.193]) by localhost (developer.postgresql.org [64.117.224.193:10024]) (amavisd-new) with ESMTP id 66377-09 for ; Mon, 19 May 2003 19:29:41 -0400 (EDT) Received: from davinci.ethosmedia.com (unknown [209.10.40.251]) by developer.postgresql.org (Postfix) with ESMTP id 3736B9258DC for ; Mon, 19 May 2003 18:05:27 -0400 (EDT) Received: from [216.135.165.74] (HELO temoku) by davinci.ethosmedia.com (CommuniGate Pro SMTP 4.0.2) with ESMTP id 3047721; Mon, 19 May 2003 15:05:29 -0700 Content-Type: text/plain; charset="iso-8859-1" From: Josh Berkus Reply-To: josh@agliodbs.com Organization: Aglio Database Solutions To: Jeff Boes , pgsql-sql@postgresql.org Subject: Re: Performance on temp table inserts Date: Mon, 19 May 2003 15:04:58 -0700 User-Agent: KMail/1.4.3 References: In-Reply-To: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Message-Id: <200305191504.58368.josh@agliodbs.com> X-Virus-Scanned: by amavisd-new X-Archive-Number: 200305/371 X-Sequence-Number: 13536 Jeff, > Box #1 is our "production" server, and actually has more going on during > the day than #2 which is the "test" server. #1 has "shared_buffers" set > to 131072; #2 has it at 250000. Hardware, O/S and PostgreSQL versions are > all identical. Software executing the query (Perl code using DBI) is the > same. First, I think you need to join the PGSQL-PERFORMANCE list; we discuss thin= gs=20 like your issue all the time there. Collective wisdom on that list is that shared_buffer settings above 5000-60= 00=20 actually degrade performance by robbing the kernel buffer of resources. Th= e=20 postgres shared_buffers are just a "holding area" for operations spooling t= o=20 the kernel buffer which actually does most of the work. HTH. --=20 -Josh Berkus Aglio Database Solutions San Francisco