Received: from localhost (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id C9A1B64FD2F for ; Fri, 5 Dec 2008 19:00:57 -0400 (AST) 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 14170-05 for ; Fri, 5 Dec 2008 19:00:55 -0400 (AST) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.179]) by mail.postgresql.org (Postfix) with ESMTP id 3FE2464FC46 for ; Fri, 5 Dec 2008 19:00:55 -0400 (AST) Received: by wa-out-1112.google.com with SMTP id j4so97437wah.19 for ; Fri, 05 Dec 2008 15:00:53 -0800 (PST) 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=eqyy6mBh5U5SmVL3sL7cM//GM7D7w3lPmWJ5JFVb/nk=; b=W6atl238ElZyG3wdS0nTCiFZlhD84SJVpUnB9KGFxlwwR58INjnUgHy2g/gltitY5L 4rzZyp5T8S0AsldK4uzU5Tv52fGlA4XYSotAhi1KnbKBJl6+Q3ydZaJB7UG2SaREjCvJ a/CTZMQ6i+8D4t1FFABAB+iT2cdtjryx9K34M= 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=EHDj8wKFuj2OIZXqhq8dIpQhru097GYd23uKDNs30gAj0WP2fMqua1q6h4xKn196xG qP1PJxWRcpC9g4ha2LLJw+PsrluPs6CdTkbwcO0xrW2GmSe/kOIMh7nrb3CsAaHFSlep XgVQxKvfsDguh0QZZ31YjSOHCq636aBoyIutY= Received: by 10.114.194.1 with SMTP id r1mr441497waf.18.1228518053846; Fri, 05 Dec 2008 15:00:53 -0800 (PST) Received: by 10.114.133.4 with HTTP; Fri, 5 Dec 2008 15:00:53 -0800 (PST) Message-ID: Date: Fri, 5 Dec 2008 16:00:53 -0700 From: "Scott Marlowe" To: "Mario Weilguni" Subject: Re: Experience with HP Smart Array P400 and SATA drives? Cc: pgsql-performance@postgresql.org In-Reply-To: <4934FE60.30702@sime.com> MIME-Version: 1.0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <4934FE60.30702@sime.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: 200812/45 X-Sequence-Number: 32081 On Tue, Dec 2, 2008 at 2:22 AM, Mario Weilguni wrote: > Has anyone benchmarked this controller (PCIe/4x, 512 MB BBC)? We try to u= se > it with 8x SATA 1TB drives in RAID-5 mode under Linux, and measure strang= e > values. An individual drive is capable of delivering 91 MB/sec sequential > read performance, and we get values ~102MB/sec out of a 8-drive RAID5, se= ems > to be ridiculous slow. Write performance seems to be much better, ~300 MB > /sec - seems ok to me. > > I guess I must be doing something wrong, I cannot believe that a 500 =80 > controller is delivering such poor performance. A few suggestions... Try to find the latest driver for your card, try using the card as nothing but a caching controller and run your RAID on software in linux (or whatever IS you're on). Test a 2 drive RAID-0 to see what kind of performance increase you get. If you can't dd a big file off of a RAID-0 at about 2x the rate of a single drive then something IS wrong with it. Try RAID 10. Try RAID-1 sets on the controller and RAID 0 over that in software.