Received: from localhost (maia-4.hub.org [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 2ED809FC172 for ; Fri, 20 Jul 2007 15:24:05 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 52711-03 for ; Fri, 20 Jul 2007 15:23:58 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by postgresql.org (Postfix) with ESMTP id 70CE79FC178 for ; Fri, 20 Jul 2007 15:23:56 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.1/8.14.1) with ESMTP id l6KINq4N012003; Fri, 20 Jul 2007 14:23:52 -0400 (EDT) To: "Jignesh K. Shah" cc: Josh Berkus , pgsql-performance@postgresql.org, Alvaro Herrera Subject: Re: User concurrency thresholding: where do I look? In-reply-to: <46A0FA31.2080208@sun.com> References: <200707190828.59088.josh@agliodbs.com> <200707191819.13899.josh@agliodbs.com> <15685.1184895926@sss.pgh.pa.us> <200707192138.39679.josh@agliodbs.com> <46A0FA31.2080208@sun.com> Comments: In-reply-to "Jignesh K. Shah" message dated "Fri, 20 Jul 2007 14:08:49 -0400" Date: Fri, 20 Jul 2007 14:23:51 -0400 Message-ID: <12002.1184955831@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200707/269 X-Sequence-Number: 25953 "Jignesh K. Shah" writes: > There are no hard failures reported anywhere. Log min durations does > show that queries are now slowing down and taking longer. > OS is not swapping and also eliminated IO by putting the whole database > on /tmp Hmm. Do you see any evidence of a context swap storm (ie, a drastic increase in the context swaps/second reading reported by vmstat)? regards, tom lane