Received: from localhost (maia-3.hub.org [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id D7A3C9FBE0D for ; Wed, 30 May 2007 17:19:08 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 86433-08 for ; Wed, 30 May 2007 17:19:05 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from chip2og51.obsmtp.com (chip2og51.obsmtp.com [64.18.13.39]) by postgresql.org (Postfix) with SMTP id DB9C59FBF30 for ; Wed, 30 May 2007 17:19:07 -0300 (ADT) Received: from source ([63.240.6.44]) (using TLSv1) by chip2ob51.postini.com ([64.18.5.12]) with SMTP; Wed, 30 May 2007 13:18:52 PDT Received: from 172.16.1.23 by mail.mi8.com with ESMTP (- Welcome to Mi8 Corporation www.Mi8.com (D4)); Wed, 30 May 2007 16:18:45 -0400 X-Server-Uuid: C8FB4D43-1108-484A-A898-3CBCC7906230 Received: from MI8NYCMAIL08.Mi8.com ([172.16.1.165]) by d01smtp09.Mi8.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 30 May 2007 16:18:45 -0400 Received: from 63.80.24.130 ([63.80.24.130]) by MI8NYCMAIL08.Mi8.com ( [172.16.1.190]) via Exchange Front-End Server mi8owa.mi8.com ( [172.16.1.134]) with Microsoft Exchange Server HTTP-DAV ; Wed, 30 May 2007 20:18:11 +0000 User-Agent: Microsoft-Entourage/11.3.3.061214 Date: Wed, 30 May 2007 13:18:09 -0700 Subject: Re: setting up raid10 with more than 4 drives From: "Luke Lonergan" To: mark@mark.mielke.cc cc: "Michael Stone" , pgsql-performance@postgresql.org Message-ID: Thread-Topic: [PERFORM] setting up raid10 with more than 4 drives Thread-Index: Acei96Ot4gMMUA7qEdy5oAAX8s8Cag== In-Reply-To: <20070530155733.GA18830@mark.mielke.cc> MIME-Version: 1.0 X-OriginalArrivalTime: 30 May 2007 20:18:45.0151 (UTC) FILETIME=[B9394AF0:01C7A2F7] X-WSS-ID: 6A4303AF1AG15599420-01-01 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200705/628 X-Sequence-Number: 25018 Mark, On 5/30/07 8:57 AM, "mark@mark.mielke.cc" wrote: > One part is corruption. Another is ordering and consistency. ZFS represents > both RAID-style storage *and* journal-style file system. I imagine consistency > and ordering is handled through journalling. Yep and versioning, which answers PFC's scenario. Short answer: ZFS has a very reliable model that uses checksumming and journaling along with block versioning to implement "self healing". There are others that do some similar things with checksumming on the SAN HW and cooperation with the filesystem. - Luke