X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id C847C9FA38F for ; Tue, 13 Jun 2006 20:12:35 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 42379-07 for ; Tue, 13 Jun 2006 20:12:30 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from smtp1.ActiveState.com (gw.activestate.com [209.17.183.249]) by postgresql.org (Postfix) with ESMTP id 949719FA1A8 for ; Tue, 13 Jun 2006 20:12:30 -0300 (ADT) Received: from smtp3.activestate.com (smtp3.activestate.com [192.168.3.19]) by smtp1.ActiveState.com (8.12.10/8.12.10) with ESMTP id k5DNCQQG012077; Tue, 13 Jun 2006 16:12:26 -0700 (envelope-from mischa@ca.sophos.com) Received: from [192.168.99.210] (mallet.activestate.com [192.168.99.210]) by smtp3.ActiveState.com (8.13.4/8.13.4) with ESMTP id k5DNCQId017595; Tue, 13 Jun 2006 16:12:26 -0700 (envelope-from mischa@ca.sophos.com) Message-ID: <448F4842.4010305@ca.sophos.com> Date: Tue, 13 Jun 2006 16:20:34 -0700 From: Mischa Sandberg Reply-To: mischa@ca.sophos.com User-Agent: Thunderbird 1.5.0.4 (X11/20060516) MIME-Version: 1.0 To: "Jim C. Nasby" CC: pgsql-performance@postgresql.org Subject: Re: Solaris shared_buffers anomaly? References: <1150151282.14661.42.camel@tigger> <20060613000441.GI8588@kenobi.snowman.net> <20060613200810.GZ34196@pervasive.com> <448F3A6E.6080908@ca.sophos.com> <20060613224759.GM34196@pervasive.com> In-Reply-To: <20060613224759.GM34196@pervasive.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200606/227 X-Sequence-Number: 19584 Jim C. Nasby wrote: > On Tue, Jun 13, 2006 at 03:21:34PM -0700, Mischa Sandberg wrote: >> Raised shared_buffers to 16000 (128MB). >> DB server dropped to a CRAWL. >> >> vmstat showed that it was swapping like crazy. >> Dropped shared_buffers back down again. >> Swapping stopped. > > What's sort_mem set to? I suspect you simply ran the machine out of > memory. 8192 (8MB). No issue when shared_buffers was 2000; same apps always. > Also, Solaris by default will only use a portion of memory for > filesystem caching, which will kill PostgreSQL performance. Yep, tested /etc/system segmap_percent at 20,40,60. No significant difference between 20 and 60. Default is 10%? 12%? Can't recall. Was not changed from 20 during the shared_buffer test. -- Engineers think that equations approximate reality. Physicists think that reality approximates the equations. Mathematicians never make the connection.