From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mingming Cao Subject: Re: [RFC 0/13] extents and 48bit ext3 Date: Fri, 09 Jun 2006 08:23:08 -0700 Message-ID: <4489925C.4010508@us.ibm.com> References: <1149816055.4066.60.camel@dyn9047017069.beaverton.ibm.com> <200606090240.k592enXj009395@turing-police.cc.vt.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-fsdevel@vger.kernel.org, ext2-devel , linux-kernel@vger.kernel.org Return-path: To: Valdis.Kletnieks@vt.edu In-Reply-To: <200606090240.k592enXj009395@turing-police.cc.vt.edu> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: ext2-devel-bounces@lists.sourceforge.net Errors-To: ext2-devel-bounces@lists.sourceforge.net List-Id: linux-fsdevel.vger.kernel.org Valdis.Kletnieks@vt.edu wrote: > On Thu, 08 Jun 2006 18:20:54 PDT, Mingming Cao said: > >>Current ext3 filesystem is limited to 8TB(4k block size), this is >>practically not enough for the increasing need of bigger storage as >>disks in a few years (or even now). >> >>To address this need, there are co-effort from RedHat, ClusterFS, IBM >>and BULL to move ext3 from 32 bit filesystem to 48 bit filesystem, >>expanding ext3 filesystem limit from 8TB today to 1024 PB. The 48 bit >>ext3 is build on top of extent map changes for ext3, originally from >>Alex Tomas. In short, the new ext3 on-disk extents format is: > > > which implies matching changes to mkfs.ext2 and possibly mount.. > > Alexandre Ratchov and Laurent Vivier from BULL have been done some work in e2fsprog to support extents and 48/64 bit ext3, although the patches have not been thoroughly reviewed and discussed yet... http://marc.theaimsgroup.com/?l=ext2-devel&m=114848122624510&w=2 >>Appreciate any comments and feedbacks! > > > Somebody else was recently discussing a set of patches to ext3 for > extents+delalloc+mballoc patches - is this work compatible with that? > Yes, the extents patch you mentioned is the same one included in the series. The delalloc (support delayed allocation for ext3) and mballoc ( support multiple block allocation based on extents) are considered a future to add, as this series is intend to address the capability issue and on-disk format only. > Also, a pointer to the matching userspace patches would help anybody > who's gung-ho enough to test the code.... > Thanks for your interest! We have tested patch 1-4 (which basically not touching any on-disk format) and they have been in mm tree. Extent patch itself have been tested for a long time by ClusterFS and IBM, as it's actually being posted a while back. At this point the whole series pass compile, but not being tested yet. This post as a RFC is intend to collect comments and feedbacks. BULL team has done some test on the 2.6.16 version of the series with the e2fsprog changes they posted though. I will upload the matching e2fsprogs changes to ext2.sf.net/48bitsext3 shortly.. Mingming