Received: from magus.postgresql.org (magus.postgresql.org [87.238.57.229]) by mail.postgresql.org (Postfix) with ESMTP id 77FF123D696 for ; Mon, 23 Jul 2012 10:53:58 -0300 (ADT) Received: from relay3-d.mail.gandi.net ([217.70.183.195]) by magus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1StJ56-0004Rc-DY for pgsql-performance@postgresql.org; Mon, 23 Jul 2012 13:53:57 +0000 X-Originating-IP: 217.70.178.132 Received: from mfilter5-d.gandi.net (mfilter5-d.gandi.net [217.70.178.132]) by relay3-d.mail.gandi.net (Postfix) with ESMTP id B9F2FA80C8; Mon, 23 Jul 2012 15:53:28 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at mfilter5-d.gandi.net Received: from relay3-d.mail.gandi.net ([217.70.183.195]) by mfilter5-d.gandi.net (mfilter5-d.gandi.net [10.0.15.180]) (amavisd-new, port 10024) with ESMTP id wjdBop-CPyaB; Mon, 23 Jul 2012 15:53:27 +0200 (CEST) X-Originating-IP: 98.27.54.176 Received: from [192.168.10.146] (cpe-098-027-054-176.nc.res.rr.com [98.27.54.176]) (Authenticated sender: adsend@dunslane.net) by relay3-d.mail.gandi.net (Postfix) with ESMTPSA id 000E9A80D6; Mon, 23 Jul 2012 15:53:26 +0200 (CEST) Message-ID: <500D5755.30803@dunslane.net> Date: Mon, 23 Jul 2012 09:53:25 -0400 From: Andrew Dunstan User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Jim Vanns CC: pgsql-performance@postgresql.org Subject: Re: Odd blocking (or massively latent) issue - even with EXPLAIN References: <1343032905.12579.3.camel@sys367.ldn.framestore.com> In-Reply-To: <1343032905.12579.3.camel@sys367.ldn.framestore.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -2.6 (--) X-Archive-Number: 201207/267 X-Sequence-Number: 47448 On 07/23/2012 04:41 AM, Jim Vanns wrote: > We're seeing SELECT statements and even EXPLAIN (no ANAYLZE) > statements hang indefinitely until *something* (we don't know what) > releases some kind of resource or no longer becomes a massive bottle > neck. These are the symptoms. I have seen this sort of behaviour on systems with massive catalogs (millions of tables and indexes). Could that be your problem? cheers andrew