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 03A5F52809 for ; Fri, 27 May 2005 09:52:20 -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 50238-05 for ; Fri, 27 May 2005 12:52:15 +0000 (GMT) Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.198]) by svr1.postgresql.org (Postfix) with ESMTP id 80C4C5280B for ; Fri, 27 May 2005 09:52:14 -0300 (ADT) Received: by wproxy.gmail.com with SMTP id 68so1775441wra for ; Fri, 27 May 2005 05:52:16 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=h/UUua+5+mvEX0S5ooLaELEGf0U51mGrMqe+X407+6X/sfQbLj2/DV1KnkKhq3ImSeij/P/0FW7+SWokIYmldsDvkNO9rL4LVdCuFTzs5Jg8B7zKxN6xK4Ivfnaq+wsohqXJ1U9HDqgNmV3XpdUHMP7sKdNODlF3tIGsmwHrG8A= Received: by 10.54.47.1 with SMTP id u1mr2516521wru; Fri, 27 May 2005 05:52:16 -0700 (PDT) Received: by 10.54.2.45 with HTTP; Fri, 27 May 2005 05:52:16 -0700 (PDT) Message-ID: <4a0cafe205052705526fccfe75@mail.gmail.com> Date: Fri, 27 May 2005 07:52:16 -0500 From: Josh Close Reply-To: Josh Close To: POSTGRES-PERFORMANCE Subject: Re: slow queries, possibly disk io In-Reply-To: <42963C3F.4000905@arbash-meinel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <4a0cafe205052613242e0d4d10@mail.gmail.com> <42963C3F.4000905@arbash-meinel.com> X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.304 tagged_above=0 required=5 tests=AWL, DNS_FROM_RFC_ABUSE, RCVD_BY_IP X-Spam-Level: X-Archive-Number: 200505/407 X-Sequence-Number: 12571 > Setting shared buffers above something like 10-30% of memory is counter > productive. What is the reason behind it being counter productive? If shared buffers are at 30%, should effective cache size be at 70%? How do those two relate? >=20 > Increasing sort_mem can help with various activities, but increasing it > too much can cause you to swap, which kills performance. The caution is > that you will likely use at least 1 sort_mem per connection, and can > likely use more than one if the query is complicated. I have a max of 100 connections and 2 gigs of mem. Right now the sort mem is a 4 megs. How much higher could I put that? -Josh