Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VJNKh-0007XM-8L for pgsql-performance@arkaria.postgresql.org; Tue, 10 Sep 2013 12:46:15 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1VJNKg-0006WM-Cv for pgsql-performance@arkaria.postgresql.org; Tue, 10 Sep 2013 12:46:14 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VJNKd-0006SR-OV for pgsql-performance@postgresql.org; Tue, 10 Sep 2013 12:46:11 +0000 Received: from relay5-d.mail.gandi.net ([217.70.183.197]) by magus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VJNKX-0005cw-Db for pgsql-performance@postgresql.org; Tue, 10 Sep 2013 12:46:11 +0000 Received: from mfilter15-d.gandi.net (mfilter15-d.gandi.net [217.70.178.143]) by relay5-d.mail.gandi.net (Postfix) with ESMTP id 8709E41C07C; Tue, 10 Sep 2013 14:45:40 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at mfilter15-d.gandi.net Received: from relay5-d.mail.gandi.net ([217.70.183.197]) by mfilter15-d.gandi.net (mfilter15-d.gandi.net [10.0.15.180]) (amavisd-new, port 10024) with ESMTP id SQh3bf+Cc69r; Tue, 10 Sep 2013 14:45:38 +0200 (CEST) X-Originating-IP: 98.27.58.255 Received: from [192.168.10.146] (cpe-098-027-058-255.nc.res.rr.com [98.27.58.255]) (Authenticated sender: adsend@dunslane.net) by relay5-d.mail.gandi.net (Postfix) with ESMTPSA id 9BBDD41C05C; Tue, 10 Sep 2013 14:45:34 +0200 (CEST) Message-ID: <522F146D.2070908@dunslane.net> Date: Tue, 10 Sep 2013 08:45:33 -0400 From: Andrew Dunstan User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Andres Freund CC: Jeff Janes , Josh Berkus , Amit Kapila , "pgsql-performance@postgresql.org" Subject: Re: Performance bug in prepared statement binding in 9.2? References: <51A699E6.3000008@agliodbs.com> <51A79512.4020200@agliodbs.com> <51FAA1B8.6040809@agliodbs.com> <522E69F1.8070203@dunslane.net> <20130910122036.GF1024477@alap2.anarazel.de> In-Reply-To: <20130910122036.GF1024477@alap2.anarazel.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -2.6 (--) 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 On 09/10/2013 08:20 AM, Andres Freund wrote: > A backtrace for this would be useful. Alternatively you could recompile > postgres using -fno-omit-frame-pointer in CFLAGS and use perf record -g. It's using a custom build, so this should be doable. > > Any chance you have older prepared xacts, older sessions or something > like that around? I'd expect heap_prune* to be present in workloads that > spend significant time in heap_hot_search_buffer... Not sure about prepared transactions. There are certainly probably old prepared statements around, and long running transactions alongside this one. cheers andrew -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance