From: Andreas Dilger Subject: Re: Something wrong with extent-based journal creation Date: Wed, 17 Jun 2009 02:04:32 -0600 Message-ID: <20090617080432.GC13073@webber.adilger.int> References: <4A381EC8.4010202@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; CHARSET=US-ASCII Content-Transfer-Encoding: 7BIT Cc: ext4 development To: Eric Sandeen Return-path: Received: from sca-es-mail-2.Sun.COM ([192.18.43.133]:49331 "EHLO sca-es-mail-2.sun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752556AbZFQIEp (ORCPT ); Wed, 17 Jun 2009 04:04:45 -0400 Received: from fe-sfbay-09.sun.com ([192.18.43.129]) by sca-es-mail-2.sun.com (8.13.7+Sun/8.12.9) with ESMTP id n5H84imd011977 for ; Wed, 17 Jun 2009 01:04:48 -0700 (PDT) Content-disposition: inline Received: from conversion-daemon.fe-sfbay-09.sun.com by fe-sfbay-09.sun.com (Sun Java(tm) System Messaging Server 7u2-7.02 64bit (built Apr 16 2009)) id <0KLD00700IDAW500@fe-sfbay-09.sun.com> for linux-ext4@vger.kernel.org; Wed, 17 Jun 2009 01:04:44 -0700 (PDT) In-reply-to: <4A381EC8.4010202@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Jun 16, 2009 17:38 -0500, Eric Sandeen wrote: > I've narrowed it down to the commit (961306d3) which creates the journal > with extent format; if that's commented out, it works fine. Hmm, this seems like it might be a troublesome feature... Are we sure that there is proper kernel/tool compatibility for an extent-mapped journal? At least none of the Lustre code has any support for this, though they can handle the INCOMPAT_EXTENTS feature, and I don't think this was present in older kernels either. I haven't looked at the code for this yet, so it may be that it will "just work", but if this is a new feature I would urge caution w.r.t. compatibility before this is merged upstream (in either e2fsprogs or the kernel). Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc.