From: Timothy Shimmin Subject: Re: [PATCH 0/4] (RESEND) ext3[34] barrier changes Date: Tue, 20 May 2008 13:29:28 +1000 Message-ID: <48324598.4060803@sgi.com> References: <482DDA56.6000301@redhat.com> <200805191439.36577.chris.mason@oracle.com> <20080519223959.GA14602@atrey.karlin.mff.cuni.cz> <200805192029.21688.chris.mason@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Jan Kara , Andrew Morton , Eric Sandeen , Theodore Tso , Andi Kleen , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org To: Chris Mason Return-path: Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:40195 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756380AbYETD3x (ORCPT ); Mon, 19 May 2008 23:29:53 -0400 In-Reply-To: <200805192029.21688.chris.mason@oracle.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi Chris, Chris Mason wrote: > On Monday 19 May 2008, Jan Kara wrote: >>> On Monday 19 May 2008, Chris Mason wrote: >>>> Here's a test workload that corrupts ext3 50% of the time on power fail >>>> testing for me. The machine in this test is my poor dell desktop >>>> (3ghz, dual core, 2GB of ram), and the power controller is me walking >>>> over and ripping the plug out the back. >>> Here's a new version that still gets about corruptions 50% of the time, >>> but does it with fewer files by using longer file names (240 chars >>> instead of 160 chars). >>> >>> I tested this one with a larger FS (40GB instead of 2GB) and larger log >>> (128MB instead of 32MB). barrier-test -s 32 -p 1500 was still able to >>> get a 50% corruption rate on the larger FS. >> Hmm, this is worse than I'd have expected :( If it is that bad, I >> think we should really enable them by default... I can give your script >> a try on my test machine when I get back (which is next week). > > That would be great, I'd like to confirm that my machine isn't the only one on > the planet so easily broken ;) > > I was also able to trigger corruptions on XFS (one run out of two), so it is > unlikely I'm seeing bugs in the ext3 replay or logging code. > Just to clarify, was this test with barriers on or off for XFS? I'm wondering if it was with barriers on, then we have a reproducible bug in log replay. Or whether you were just confirming the problems with barriers off on another filesystem. Thanks muchly, Tim.