Received: from maia.hub.org (maia-3.hub.org [200.46.204.243]) by mail.postgresql.org (Postfix) with ESMTP id A74F3632BCA for ; Wed, 2 Jun 2010 20:41:04 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.243]) (amavisd-maia, port 10024) with ESMTP id 93916-01 for ; Wed, 2 Jun 2010 23:40:52 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.catalyst.net.nz (bertrand.catalyst.net.nz [202.78.240.40]) by mail.postgresql.org (Postfix) with ESMTP id 2523D6323AE for ; Wed, 2 Jun 2010 20:40:52 -0300 (ADT) Received: from localhost (localhost [127.0.0.1]) by mail.catalyst.net.nz (Postfix) with ESMTP id 1FDFF338C2 for ; Thu, 3 Jun 2010 11:40:50 +1200 (NZST) X-Virus-Scanned: Debian amavisd-new at catalyst.net.nz Received: from mail.catalyst.net.nz ([127.0.0.1]) by localhost (bertrand.catalyst.net.nz [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KIdMl8YPfKuZ for ; Thu, 3 Jun 2010 11:40:49 +1200 (NZST) Received: from [IPv6:2404:130:0:1000:222:15ff:fe5c:2471] (unknown [IPv6:2404:130:0:1000:222:15ff:fe5c:2471]) (Authenticated sender: mark.kirkwood) by mail.catalyst.net.nz (Postfix) with ESMTPSA id 826756839F for ; Thu, 3 Jun 2010 11:40:49 +1200 (NZST) Message-ID: <4C06EC01.3060506@catalyst.net.nz> Date: Thu, 03 Jun 2010 11:40:49 +1200 From: Mark Kirkwood User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100423 Thunderbird/3.0.4 MIME-Version: 1.0 To: pgsql-performance@postgresql.org Subject: Re: Weird XFS WAL problem References: <4C06E994.2080905@emolecules.com> In-Reply-To: <4C06E994.2080905@emolecules.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.79 tagged_above=-10 required=5 tests=BAYES_50=0.8, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201006/48 X-Sequence-Number: 38904 On 03/06/10 11:30, Craig James wrote: > I'm testing/tuning a new midsize server and ran into an inexplicable > problem. With an RAID10 drive, when I move the WAL to a separate > RAID1 drive, TPS drops from over 1200 to less than 90! I've checked > everything and can't find a reason. > > Are the 2 new RAID1 disks the same make and model as the 12 RAID10 ones? Also, are barriers *on* on the RAID1 mount and off on the RAID10 one? Cheers Mark