Received: from localhost (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id EA8E6632874 for ; Mon, 27 Apr 2009 00:28:21 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 30219-05 for ; Mon, 27 Apr 2009 00:28:13 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from yx-out-2324.google.com (yx-out-2324.google.com [74.125.44.30]) by mail.postgresql.org (Postfix) with ESMTP id AF01D63230C for ; Mon, 27 Apr 2009 00:28:13 -0300 (ADT) Received: by yx-out-2324.google.com with SMTP id 8so1475764yxg.73 for ; Sun, 26 Apr 2009 20:28:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=1oRmrONsptan8L3iU8e4LbT4YltqYiXUF6dwtOZitK4=; b=BoxTHC9oi3KIDEY6tQA2R7QLfBQ5yq01UP/U75aUP3PLzZfF3INAkvACorZTc5F1/3 67VpddoOG8vc5eOdOP5Qjz/84HPYOC9fxedSIttIOKwLwAhXpONPSm2mcBkEo5Jsm/bP nCRoAFlPoQcTPBAHvG3Y2sXP1KiaP6ECUZfRI= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=aicmiKJj0HIgKBRdmDt+aF9ZrCkQYbM9N2Ly4MA/HHIFXSMcqbBU3RpFHmQX4iQcl5 U520HnKffk6Ssht+bfG/7fQjufwtear8M2Y3qM38yiuy/u9txJVT33XIgwvooaTaXPzl 66w5l+UYbTY2alNjJ2thWz1cFnhzsUF+LgpoI= MIME-Version: 1.0 Received: by 10.100.8.4 with SMTP id 4mr7681164anh.146.1240802893094; Sun, 26 Apr 2009 20:28:13 -0700 (PDT) In-Reply-To: <70c01d1d0904111144m50c569bbh7dc32f2bce36195e@mail.gmail.com> References: <70c01d1d0904111144m50c569bbh7dc32f2bce36195e@mail.gmail.com> Date: Sun, 26 Apr 2009 20:28:13 -0700 Message-ID: <70c01d1d0904262028j42fc4940s116fc14ec26d2e35@mail.gmail.com> Subject: Re: Using IOZone to simulate DB access patterns From: Mark Wong To: Greg Smith Cc: Scott Carey , Josh Berkus , henk de wit , "jesper@krogh.cc" , "pgsql-performance@postgresql.org" , Selena Deckelmann , Gabrielle Roth Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none X-Spam-Level: X-Archive-Number: 200904/379 X-Sequence-Number: 33746 On Sat, Apr 11, 2009 at 11:44 AM, Mark Wong wrote: > On Fri, Apr 10, 2009 at 11:01 AM, Greg Smith wrote= : >> On Fri, 10 Apr 2009, Scott Carey wrote: >> >>> FIO with profiles such as the below samples are easy to set up >> >> There are some more sample FIO profiles with results from various >> filesystems at >> http://wiki.postgresql.org/wiki/HP_ProLiant_DL380_G5_Tuning_Guide > > There's a couple of potential flaws I'm trying to characterize this > weekend. =A0I'm having second thoughts about how I did the sequential > read and write profiles. =A0Using multiple processes doesn't let it > really do sequential i/o. =A0I've done one comparison so far resulting > in about 50% more throughput using just one process to do sequential > writes. =A0I just want to make sure there shouldn't be any concern for > being processor bound on one core. > > The other flaw is having a minimum run time. =A0The max of 1 hour seems > to be good to establishing steady system utilization, but letting some > tests finish in less than 15 minutes doesn't provide "good" data. > "Good" meaning looking at the time series of data and feeling > confident it's a reliable result. =A0I think I'm describing that > correctly... FYI, I've updated the wiki with the parameters I'm running with now. I haven't updated the results yet though. Regards, Mark