Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 2DCA96500DD for ; Fri, 8 Aug 2008 13:44:40 -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 78346-08 for ; Fri, 8 Aug 2008 13:44:34 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from nf-out-0910.google.com (nf-out-0910.google.com [64.233.182.190]) by postgresql.org (Postfix) with ESMTP id E2822650080 for ; Fri, 8 Aug 2008 13:44:34 -0300 (ADT) Received: by nf-out-0910.google.com with SMTP id c7so368354nfi.23 for ; Fri, 08 Aug 2008 09:44:33 -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=tZumpDXa20ZU46YxA5mUfj2okTWdJySITnFUu64+Bnw=; b=l9nS5XtLb33FwWUcF6e32T76D8oCbinntbONTW0Ymft3YD9/5ofoo14KrkIJs0zRPy 0VzbsCsIB9Bn4BxYT/dvBCpJRLJ9fbTmwsg1+Tgjxuq0FjD20R02tGIXpxg/xDE3i/Z4 EdocPbII+L5o6/ApR8fTXHjMivOav5sLNHzr0= 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=rwcVNs3UPMZqxioJexcCgpHzj7UHyvMbZnTQIzge126RXGDqj93rN0qkVTqZoUZUYT fdA7nai+rzUTgHMw5nATHDe9SQpkts7ICRSVhT3zaQKyFj1hPLEgOeeaRqeX8SN0aBIZ n2Qo32Z8DlR72j+qZwsXuDJgpbxwVzZ38TaHI= Received: by 10.210.105.20 with SMTP id d20mr5766374ebc.18.1218213873373; Fri, 08 Aug 2008 09:44:33 -0700 (PDT) Received: by 10.210.72.10 with HTTP; Fri, 8 Aug 2008 09:44:33 -0700 (PDT) Message-ID: <70c01d1d0808080944v4cd985d6r75b5e46ed720bdf7@mail.gmail.com> Date: Fri, 8 Aug 2008 09:44:33 -0700 From: "Mark Wong" To: Henrik Subject: Re: Filesystem benchmarking for pg 8.3.3 server Cc: "Luke Lonergan" , 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: <014F2941B0A1EA47BD61D21526B806E903509704@MI8NYCMAIL08.Mi8.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: 200808/74 X-Sequence-Number: 30955 On Fri, Aug 8, 2008 at 8:08 AM, Henrik wrote: > But random writes should be faster on a RAID10 as it doesn't need to > calculate parity. That is why people suggest RAID 10 for datases, correct? > I can understand that RAID5 can be faster with sequential writes. There is some data here that does not support that RAID5 can be faster than RAID10 for sequential writes: http://wiki.postgresql.org/wiki/HP_ProLiant_DL380_G5_Tuning_Guide Regards, Mark