From: "Amir G." Subject: Re: Introducing Next3 - built-in snapshots support for Ext3 Date: Sun, 9 May 2010 00:56:11 +0200 Message-ID: References: <20100504224226.GE6344@thunk.org> <87vdaz21b0.fsf@basil.nowhere.org> <4BE4855E.40808@redhat.com> <4BE55E49.5000006@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: Andi Kleen , tytso@mit.edu, linux-ext4@vger.kernel.org To: Ric Wheeler Return-path: Received: from mail-bw0-f219.google.com ([209.85.218.219]:40846 "EHLO mail-bw0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750868Ab0EHW4N (ORCPT ); Sat, 8 May 2010 18:56:13 -0400 Received: by bwz19 with SMTP id 19so1151990bwz.21 for ; Sat, 08 May 2010 15:56:11 -0700 (PDT) In-Reply-To: <4BE55E49.5000006@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sat, May 8, 2010 at 2:51 PM, Ric Wheeler wrote: > On 05/08/2010 01:43 AM, Amir G. wrote: > > As Ted mentioned in his reply, the big concern is that you are forking ext3 > instead of adding a new feature to the end of the ext* family of file > systems. > That is a valid concern, but this is where Next3 stands today. There is no intention of replacing Ext4 with Next4 as the leading ext* f/s. The branch from Ext3 was made at the time to speed up the development process of the snapshot feature. > Since we have multiple snapshot mechanisms in place already (not just btrfs > & lvm, but don't forget all of the builtin array snapshots), I think that we > are not in a hurry to get this done quickly. I would strongly prefer we get > this rebased onto the latest ext4 and resubmitted. > If I were you I would also prefer to get snapshots in ext4, and even snapshots along side extent mapped files, but unfortunately, I cannot promise to deliver either anytime soon. I can only promise my support to anyone who wishes to participate in the merge task. > As far as proof goes, I think that the unfortunate burden of proof is on > your shoulders to prove to us that we should take and maintain those new > features given the often conflicting priorities :-) > What can I say, a Windows file server can display previous file versions without using a costly storage array. Can a RedHat server do that? Can LVM snapshots be used to do that? The CTERA NAS appliances do that using Next3. Amir.