Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 43BC71194B01 for ; Tue, 15 Nov 2011 20:19:27 -0400 (AST) 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 93318-01-4 for ; Wed, 16 Nov 2011 00:19:19 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0-rc2 Received: from makus.postgresql.org (makus.postgresql.org [98.129.198.125]) by mail.postgresql.org (Postfix) with ESMTP id 1B575F48CCA for ; Tue, 15 Nov 2011 20:19:10 -0400 (AST) Received: from mail.gransy.com ([82.208.29.194]) by makus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1RQTDX-0004OK-BS for pgsql-performance@postgresql.org; Wed, 16 Nov 2011 00:19:10 +0000 Received: from antispam.gransy.com (antispam.gransy.com [77.78.104.124]) by mail.gransy.com (Postfix) with ESMTP id 000F64A2095 for ; Wed, 16 Nov 2011 01:18:52 +0100 (CET) Received: from mail.gransy.com ([82.208.29.194]) by antispam.gransy.com (antispam.gransy.com [77.78.104.124]) (amavisd-new, port 10024) with ESMTP id x69OrncnzH7A for ; Wed, 16 Nov 2011 01:18:52 +0100 (CET) Received: from [192.168.1.237] (ip-78-45-133-255.net.upcbroadband.cz [78.45.133.255]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.gransy.com (Postfix) with ESMTPSA id D07D94A2093 for ; Wed, 16 Nov 2011 01:18:52 +0100 (CET) Message-ID: <4EC30F05.6010901@fuzzy.cz> Date: Wed, 16 Nov 2011 02:16:53 +0100 From: Tomas Vondra User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:6.0) Gecko/20110812 Thunderbird/6.0 MIME-Version: 1.0 To: pgsql-performance@postgresql.org Subject: Re: Slow queries / commits, mis-configuration or hardware issues? References: <87e450fd65045c328f41e1b99a4029d5.squirrel@sq.gransy.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-10 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201111/186 X-Sequence-Number: 45697 Dne 14.11.2011 22:58, Cody Caughlan napsal(a): > I ran bonnie++ on a slave node, doing active streaming replication but > otherwise idle: > http://batch-files-test.s3.amazonaws.com/sql03.prod.html > > bonnie++ on the master node: > http://batch-files-test.s3.amazonaws.com/sql01.prod.html > > If I am reading this right, this is my first time using it, the > numbers dont look too good. I've done some benchmarks on my own (m1.xlarge instance), and the results are these (http://pastebin.com/T1LXHru0): single drive ------------ dd writes: 62 MB/s dd reads: 110 MB/s bonnie seq. writes: 55 MB/s bonnie seq. rewrite: 33 MB/s bonnie seq. reads: 91 MB/s bonnie seeks: 370/s raid 0 (4 devices) ----------------------------- dd writes: 220 MB/s dd reads: 380 MB/s bonnie seq. writes: 130 MB/s bonnie seq. rewrite: 114 MB/s bonnie seq. reads: 280 MB/s bonnie seeks: 570/s raid 10 (4 devices) ----------------------------- dd writes: 90 MB/s dd reads: 200 MB/s bonnie seq. writes: 49 MB/s bonnie seq. rewrite: 56 MB/s bonnie seq. reads: 160 MB/s bonnie seeks: 590/s So the results are rather different from your results (both master and slave). What surprises me a bit is the decrease of write performance between sigle drive and RAID 10. I've used bonnie++ 1.03e, so I'm wondering if the 1.96 would give different results ... All those benchmarks were performed with ext3. Tomas