Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UFsrC-0004Oi-MQ for pgsql-performance@arkaria.postgresql.org; Wed, 13 Mar 2013 21:05:06 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.72) (envelope-from ) id 1UFsrC-0005pZ-0X for pgsql-performance@arkaria.postgresql.org; Wed, 13 Mar 2013 21:05:06 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UFsrB-0005oZ-79; Wed, 13 Mar 2013 21:05:05 +0000 Received: from smtp.01.com ([199.36.142.181]) by magus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UFsr6-0007Mj-Uo; Wed, 13 Mar 2013 21:05:04 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id F040A39000E; Wed, 13 Mar 2013 16:04:58 -0500 (CDT) X-Virus-Scanned: amavisd-new at smtp-out-2.01.com Received: from smtp.01.com ([127.0.0.1]) by localhost (smtp-out-2.01.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id sUK0p6D3CKfQ; Wed, 13 Mar 2013 16:04:58 -0500 (CDT) Received: from smtp.01.com (localhost.localdomain [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id C4D88390069; Wed, 13 Mar 2013 16:04:58 -0500 (CDT) Received: from mail-1.01.com (mail.01.com [172.18.30.178]) by smtp-out-2.01.com (Postfix) with ESMTP id A07EB39000E; Wed, 13 Mar 2013 16:04:58 -0500 (CDT) Date: Wed, 13 Mar 2013 16:04:58 -0500 (CDT) From: Joshua Berkus To: Emre Hasegeli Cc: dba@tart.com.tr, pgsql-performance@postgresql.org, pgsql Message-ID: <978553984.25691.1363208698441.JavaMail.root@agliodbs.com> In-Reply-To: Subject: Re: PostgreSQL 9.2.3 performance problem caused Exclusive locks MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [172.18.31.178] X-Mailer: Zimbra 7.2.1_GA_2790 (ZimbraWebClient - FF3.0 (Linux)/7.2.1_GA_2790) X-Pg-Spam-Score: -1.9 (-) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org Emre, > > LOG: process 4793 acquired ExclusiveLock on extension of relation > > 305605 of database 16396 after 2348.675 ms The reason you're seeing that message is that you have log_lock_waits turned on. That message says that some process waited for 2.3 seconds to get a lock for expanding the size of relation 16396/305605, which is most likely an index. This is most likely due to changes in your application, or an increase in concurrent write activity. --Josh -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance