Received: from makus.postgresql.org (makus.postgresql.org [98.129.198.125]) by mail.postgresql.org (Postfix) with ESMTP id EF02323D696 for ; Mon, 23 Jul 2012 11:47:44 -0300 (ADT) Received: from mx5.framestore.com ([193.203.83.15]) by makus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1StJvD-00042T-Df for pgsql-performance@postgresql.org; Mon, 23 Jul 2012 14:47:44 +0000 Received: from vm-zimbra.ldn.framestore.com ([172.16.73.68] helo=zimbra.framestore.com) by mx5.framestore.com with esmtp (Exim 4.72) (envelope-from ) id 1StJuy-0003wt-8c; Mon, 23 Jul 2012 15:47:29 +0100 Received: from [172.16.84.176] (sys367.ldn.framestore.com [172.16.84.176]) by zimbra.framestore.com (Postfix) with ESMTPA id A173A1E8620E; Mon, 23 Jul 2012 15:47:15 +0100 (BST) Subject: Re: Odd blocking (or massively latent) issue - even with EXPLAIN From: Jim Vanns To: Andrew Dunstan Cc: Jim Vanns , pgsql-performance@postgresql.org In-Reply-To: <500D5755.30803@dunslane.net> References: <1343032905.12579.3.camel@sys367.ldn.framestore.com> <500D5755.30803@dunslane.net> Content-Type: text/plain; charset="UTF-8" Organization: Framestore Date: Mon, 23 Jul 2012 15:47:22 +0100 Message-ID: <1343054842.12579.112.camel@sys367.ldn.framestore.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 (2.28.3-1.fc12) Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -1.9 (-) X-Archive-Number: 201207/269 X-Sequence-Number: 47450 On Mon, 2012-07-23 at 09:53 -0400, Andrew Dunstan wrote: > 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? Possibly. I'm not familiar with the catalogs. I'll look into that. Thanks, Jim > > cheers > > andrew > -- Jim Vanns Systems Programmer Framestore