Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VLvZK-0005dY-Cy for pgsql-performance@arkaria.postgresql.org; Tue, 17 Sep 2013 13:43:54 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1VLvZJ-0004BS-TP for pgsql-performance@arkaria.postgresql.org; Tue, 17 Sep 2013 13:43:53 +0000 Received: from makus.postgresql.org ([2001:4800:7903:4::125]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VLvZJ-0004BK-22 for pgsql-performance@postgresql.org; Tue, 17 Sep 2013 13:43:53 +0000 Received: from moutng.kundenserver.de ([212.227.126.187]) by makus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VLvZG-00015j-77 for pgsql-performance@postgresql.org; Tue, 17 Sep 2013 13:43:52 +0000 Received: from anarazel.de (p5DDC4CBE.dip0.t-ipconnect.de [93.220.76.190]) by mrelayeu.kundenserver.de (node=mrbap0) with ESMTP (Nemesis) id 0MfStn-1VXf1a1A55-00OmYC; Tue, 17 Sep 2013 15:43:49 +0200 Received: by anarazel.de (Postfix, from userid 1000) id 99EF1100D8A; Tue, 17 Sep 2013 15:43:48 +0200 (CEST) Date: Tue, 17 Sep 2013 15:43:48 +0200 From: Andres Freund To: Merlin Moncure Cc: =?utf-8?B?0JTQvNC40YLRgNC40Lkg0JTQtdCz0YLRj9GA0ZHQsg==?= , postgres performance list Subject: Re: Cpu usage 100% on slave. s_lock problem. Message-ID: <20130917134348.GG5452@awork2.anarazel.de> References: <20130827155556.GA9061@awork2.anarazel.de> <20130917115926.GA5452@awork2.anarazel.de> <20130917132439.GD5452@awork2.anarazel.de> <20130917133546.GE5452@awork2.anarazel.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Provags-ID: V02:K0:qKkOsxez7yb44Fxxe5iddU2SZ6101au9o4GAiRgFLIq J9viZRNfnaPh2Ygwfnej0ViQmeOwIaSI2Vs8EYxO7i9eugzm7V 3204QyIxs8+5NsB8qdn9s0aZYKglX3qgymbIfkQT3ZvJc1gu4B CewKkj6KPimV874TPOnV3cVMnpRBqkNMO90DsZChMY0Evjqz/g t26GLQN5/kA63EaIbImXR38106EP9W5nvVur3fbyG3wZlUtIT5 8pZjAjRqFEARkmXL8MfJU3Ek5/B7UtGDOTVisc2RkY6Mp776TS KW/bcNZldCoDpZzvxkhAeWCnTzVZiE1fhiio6T6sATDxKfoyrz sOOHeM4WVaVQr3pP/RLl5sglC/LDu6v4QWaCNk3t4 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 On 2013-09-17 08:40:23 -0500, Merlin Moncure wrote: > > If you ever get into the situation I mistakenly referred to again, I'd > > strongly suggest recompling postgres with -fno-omit-frame-pointer. That > > makes hierarchical profiles actually useful which can help tremendously > > with diagnosing issues like this... > > We may get an opportunity to do that. I'm curious enough about the > THP compaction issues that Kevin mentioned to to maybe consider > cranking buffers again. If I do that, it will be with strict > instructions to the site operators to catch a profile before taking > further action. The THP issues should be very clearly diagnosable because a good part of the time will be spent in the kernel. Lots of spinlocking there, but the function names are easily discernible from pg's code. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance