From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Kleikamp Subject: Re: Fix(es) for ext2 fsync bug Date: Tue, 20 Feb 2007 16:25:18 -0600 Message-ID: <1172010318.9127.5.camel@kleikamp.austin.ibm.com> References: <20070214195453.GB7521@nifty> <20070215142020.GA9930@thunk.org> <1171552162.21710.9.camel@kleikamp.austin.ibm.com> <20070220211300.GA5264@nifty> <21e789ec0702201330x1c2706b7kcd055b97cb37e0e@mail.gmail.com> <20070220213927.GG5264@nifty> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Junfeng Yang , Theodore Tso , linux-fsdevel@vger.kernel.org, Can Sar , Dawson Engler To: Valerie Henson Return-path: Received: from e6.ny.us.ibm.com ([32.97.182.146]:56130 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030500AbXBTWZY (ORCPT ); Tue, 20 Feb 2007 17:25:24 -0500 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e6.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id l1KMQ648000540 for ; Tue, 20 Feb 2007 17:26:06 -0500 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v8.2) with ESMTP id l1KMPMwK234448 for ; Tue, 20 Feb 2007 17:25:22 -0500 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l1KMPLRq032588 for ; Tue, 20 Feb 2007 17:25:22 -0500 In-Reply-To: <20070220213927.GG5264@nifty> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Tue, 2007-02-20 at 21:39 +0000, Valerie Henson wrote: > On Tue, Feb 20, 2007 at 01:30:25PM -0800, Junfeng Yang wrote: > > On 2/20/07, Valerie Henson wrote: > > > > > >Google. (GoogleFS runs on top of ext2.) > > > > It's surprising to know that... I guess they reply on GoogleFS's own > > replication and checksumming for consistency. > > Yep, they just want a local file system with ultrafast on-line > performance. They don't care about recovery time particularly because > of the GoogleFS replication (although I heard rumors they have some > fast fsck scheme, maybe resembling the dirty bit stuff I did last > year). I wonder if they would consider this a important bug? I know nothing about GoogleFS, but I would guess that they have more sophisticated recovery than relying on an fsync shortly before a crash to ensure data integrity. Shaggy -- David Kleikamp IBM Linux Technology Center