Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 05F20B5DD9A for ; Tue, 6 Sep 2011 05:32:28 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 34404-06 for ; Tue, 6 Sep 2011 08:32:21 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from aic.ai.wu-wien.ac.at (aic.ai.wu-wien.ac.at [137.208.51.5]) by mail.postgresql.org (Postfix) with ESMTP id A78E7B5DD94 for ; Tue, 6 Sep 2011 05:32:21 -0300 (ADT) Received: from localhost (localhost.localdomain [127.0.0.1]) by aic.ai.wu-wien.ac.at (Postfix) with ESMTP id 873382E5D2; Tue, 6 Sep 2011 10:32:20 +0200 (CEST) Received: from aic.ai.wu-wien.ac.at ([127.0.0.1]) by localhost (aic [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 20178-05; Tue, 6 Sep 2011 10:32:15 +0200 (CEST) Received: from [10.112.43.144] (081-003-214-196.yesss.at [81.3.214.196]) by aic.ai.wu-wien.ac.at (Postfix) with ESMTP id BF1002E5D1; Tue, 6 Sep 2011 10:32:12 +0200 (CEST) Message-ID: <4E65DA89.2030106@ai.wu.ac.at> Date: Tue, 06 Sep 2011 10:32:09 +0200 From: Gerhard Wohlgenannt User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.18) Gecko/20110617 Thunderbird/3.1.11 MIME-Version: 1.0 To: Tomas Vondra Cc: Andy Colson , pgsql-performance@postgresql.org, Heinz-Peter Lang , Gerhard Wohlgenannt , "Weichselbraun, Albert" Subject: Re: Sudden drop in DBb performance References: <4E61D6B4.9090804@ai.wu.ac.at> <33fadeb6ac1bade5ef01bd08d1fd7807.squirrel@sq.gransy.com> <4E64D3D3.8000205@squeakycode.net> <4E64D7EA.3010704@ai.wu.ac.at> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new-20030616-p10 at ai.wu-wien.ac.at X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.13 tagged_above=-10 required=5 tests=BAYES_00=-1.9, RCVD_IN_SORBS_WEB=0.77 X-Spam-Level: X-Archive-Number: 201109/60 X-Sequence-Number: 44836 hi, > What does a "normal load" mean? Does that mean a time when the queries are > slow? yes, we are have slow queries (according to postgresql.log) with such load > Are you sure the machine really has 48GB of RAM? Because from the vmstat > output it seems like there's just 32GB. > > procs -----------memory---------- ---swap-- -----io---- -system-- > ----cpu---- > r b swpd free buff cache si so bi bo in cs us sy > id wa > 0 0 1342168 336936 107636 31353512 0 0 14 183 1911 3426 > 2 1 93 4 > > > 1342168 + 336936 + 107636 + 31353512 = 33140252 ~ 31GB strange. we paid for 48G :-) and top and free show 48G /root# free total used free shared buffers cached Mem: 49564860 49310444 254416 0 30908 30329576 -/+ buffers/cache: 18949960 30614900 Swap: 20971512 1370960 19600552 > Otherwise I don't see anything wrong in the output. What is the size of > the database (use pg_database_size to get it)? Did it grow significantly > recently? > there are a number of databases in the cluster on that machine, in the filesystem it adds up to 271G cheers gerhard