Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 8511665018C for ; Thu, 7 Aug 2008 19:13:03 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 09382-04 for ; Thu, 7 Aug 2008 19:12:56 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from wf-out-1314.google.com (wf-out-1314.google.com [209.85.200.170]) by postgresql.org (Postfix) with ESMTP id 54A6665018A for ; Thu, 7 Aug 2008 19:13:00 -0300 (ADT) Received: by wf-out-1314.google.com with SMTP id 25so531942wfc.28 for ; Thu, 07 Aug 2008 15:12:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references; bh=C5p42G9fMDaI0vHcYMwzzxHifdnjH9XVhCSCzJrbotQ=; b=dgXEuZ5Nf7k4Z0B7ngpboVwQ3KN9f5IrS7airmOLpIgrUq5YxrWtZEtl7U5g5nw/S5 Pqji8K2qnGouAV0QKiOdYuS4Q82iA0ibvwbZy952PfM3KTcUQ3mLDp1Ou7Y2PIsjsNxT WjOqp96wgqhW0sq0b39xElIi+XLppNm3AJk5Q= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=oizCEj5pr3A7tH2XCkldhpH+OkOXqoWH4f97uDd7/LUPQbCrsSnDb+EZ80TSKztOB0 6Nu6Dt6iO/lQyFGe9N4cld36fuWsTj5UPRGBccJHMXbhacM+4FUm65W5XFaDUfWgZik7 dxSVV/NNNvhcECs8jt+1KZiEGC+grsRKb3g94= Received: by 10.142.174.18 with SMTP id w18mr660441wfe.202.1218147179018; Thu, 07 Aug 2008 15:12:59 -0700 (PDT) Received: by 10.142.165.13 with HTTP; Thu, 7 Aug 2008 15:12:58 -0700 (PDT) Message-ID: Date: Thu, 7 Aug 2008 16:12:58 -0600 From: "Scott Marlowe" To: "Andrej Ricnik-Bay" Subject: Re: file system and raid performance Cc: "pgsql-performance@postgresql.org" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <70c01d1d0808042154u7b78d988vac1e461a93b0ba10@mail.gmail.com> <4898E80A.3020809@paradise.net.nz> <489A3B75.6060004@paradise.net.nz> <489AC2F0.9050907@paradise.net.nz> <489ACC90.9030401@sime.com> <70c01d1d0808071236u36fe5002w833582b036d952e8@mail.gmail.com> 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: 200808/58 X-Sequence-Number: 30939 On Thu, Aug 7, 2008 at 3:57 PM, Andrej Ricnik-Bay wrote: > 2008/8/8 Scott Marlowe : >> noatime turns off the atime write behaviour. Or did you already know >> that and I missed some weird post where noatime somehow managed to >> slow down performance? > > Scott, I'm quite aware of what noatime does ... you didn't miss a post, but > if you look at Mark's graphs on > http://wiki.postgresql.org/wiki/HP_ProLiant_DL380_G5_Tuning_Guide > they pretty much all indicate that (unless I completely misinterpret the > meaning and purpose of the labels), independent of the file-system, > using noatime slows read/writes down (on average). Interesting. While a few of the benchmarks looks noticeably slower with noatime (reiserfs for instance) most seem faster in that listing. I am just now setting up our big database server for work and noticed a MUCH lower performance without noatime.