From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754372AbXDPDHS (ORCPT ); Sun, 15 Apr 2007 23:07:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754368AbXDPDHS (ORCPT ); Sun, 15 Apr 2007 23:07:18 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:36473 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754372AbXDPDHQ (ORCPT ); Sun, 15 Apr 2007 23:07:16 -0400 Date: Mon, 16 Apr 2007 13:07:05 +1000 From: David Chinner To: Rik van Riel Cc: "David R. Litwin" , linux-kernel@vger.kernel.org Subject: Re: ZFS with Linux: An Open Plea Message-ID: <20070416030705.GY32602149@melbourne.sgi.com> References: <4622C851.2030509@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4622C851.2030509@redhat.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 15, 2007 at 08:50:25PM -0400, Rik van Riel wrote: > David R. Litwin wrote: > > >>4: ZFS has a HUGE capacity. I don't have 30 exobytes, but I might some > >>day.... > > > >ext4 will probably cope with that. XFS definitely has very high > >limits though I admit I don't know what they are. > > > >XFS is also a few exobytes. > > The fsck for none of these filesystems will be able to deal with > a filesystem that big. Unless, of course, you have a few weeks > to wait for fsck to complete. Which is why I want to be able to partially offline a chunk of a filesystem and repair it while the rest is still online..... > Backup and restore are similar problems. When part of the filesystem > is lost, you don't want to have to wait for a full restore. > > Sounds simple? Well, the hard part is figuring out exactly which > part of the filesystem you need to restore... > > I don't see ZFS, ext4 or XFS addressing these issues. XFS has these sorts of issues directly in our cross-hairs. The major scaling problem XFS has right now is to do with how long repair/backup/restore take when you have hundreds of terabytes of storage. > IMHO chunkfs could provide a much more promising approach. Agreed, that's one method of compartmentalising the problem..... Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group