From: Theodore Tso Subject: Re: More ext4 acl/xattr corruption - 4th occurence now Date: Fri, 15 May 2009 08:50:35 -0400 Message-ID: <20090515125035.GC9173@mit.edu> References: <20090513062634.GE4972@kulgan> <20090514044011.GC11352@mit.edu> <20090514110659.GA5146@kulgan> <20090514132506.GD5146@kulgan> <20090514140732.GI11352@mit.edu> <20090514143014.GH5146@kulgan> <20090514161254.GJ11352@mit.edu> <20090514210244.GL5146@kulgan> <20090514212325.GG21316@mit.edu> <4A0CC381.3080804@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Kevin Shanahan , Andreas Dilger , Alex Tomas , linux-ext4@vger.kernel.org To: Eric Sandeen Return-path: Received: from thunk.org ([69.25.196.29]:55465 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753047AbZEOMum (ORCPT ); Fri, 15 May 2009 08:50:42 -0400 Content-Disposition: inline In-Reply-To: <4A0CC381.3080804@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Thu, May 14, 2009 at 08:21:05PM -0500, Eric Sandeen wrote: > > it should lay out a 4g file in random 1m direct IOs to fragment it and > get a lot of extents, then launch 2 threads, one each doing random reads > and random writes of that same file. > > I can't make this trip it, though ... If all of the blocks are in the page cache, you won't end up calling ext4_get_blocks(). Try adding a shell script which runs in parallel doing a "while /bin/true ; do sleep 1; echo 3 > /proc/sys/vm/drop_cache; done". - Ted