Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UcMHa-0000cH-5b for pgsql-admin@arkaria.postgresql.org; Tue, 14 May 2013 20:57:14 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.72) (envelope-from ) id 1UcMHZ-0006i6-L1 for pgsql-admin@arkaria.postgresql.org; Tue, 14 May 2013 20:57:13 +0000 Received: from makus.postgresql.org ([2001:4800:7903:4::125]) by malur.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UcMHY-0006hn-HE for pgsql-admin@postgresql.org; Tue, 14 May 2013 20:57:12 +0000 Received: from mail.savoirfairelinux.com ([209.172.62.77]) by makus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UcMHV-0005Cv-Vt for pgsql-admin@postgresql.org; Tue, 14 May 2013 20:57:11 +0000 Received: from localhost (localhost [127.0.0.1]) by mail.savoirfairelinux.com (Postfix) with ESMTP id 0346B10D7470 for ; Tue, 14 May 2013 16:57:07 -0400 (EDT) X-Virus-Scanned: amavisd-new at mail.savoirfairelinux.com Received: from mail.savoirfairelinux.com ([127.0.0.1]) by localhost (mail.savoirfairelinux.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id aRicxIQYbYhV for ; Tue, 14 May 2013 16:57:06 -0400 (EDT) Received: from [192.168.50.222] (mtl.savoirfairelinux.net [208.88.110.46]) by mail.savoirfairelinux.com (Postfix) with ESMTPSA id AA79910D7469 for ; Tue, 14 May 2013 16:57:06 -0400 (EDT) Message-ID: <5192A522.3040002@savoirfairelinux.com> Date: Tue, 14 May 2013 16:57:06 -0400 From: Nicolas Zin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130308 Thunderbird/17.0.4 MIME-Version: 1.0 To: pgsql-admin@postgresql.org Subject: select * from pg_stat_bgwriter slow X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -0.6 (/) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-admin Precedence: bulk Sender: pgsql-admin-owner@postgresql.org Hi, we have a postgresql 9.0, I setup collectd to gather some information. It frequently ask the database about the bgwriter state by requesting "select * from pg_stat_bgwriter" (among other stats). It seems that this requets takes 6-7s to answer and in the log we got "pgstat timeout" Note: The database is constantly loaded with insert (but not overloaded). Does someone have an idea why such request can take so long to answer. I was thinking bgwriter stats is just a matter of picking global info in memory. Can it be due to locks of some sort ? Cordialy, Nicolas Zin -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin