From: Amir Goldstein Subject: Re: [LSF/FS TOPIC] Ext4 snapshots status update Date: Fri, 4 Feb 2011 07:52:39 +0200 Message-ID: References: <20110204002043.GA15658@noexit> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE To: Amir Goldstein , lsf-pc@lists.linuxfoundation.org, linux-fsdevel , Ext4 Developers List , Theodore Tso Return-path: Received: from mail-qw0-f46.google.com ([209.85.216.46]:45428 "EHLO mail-qw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751417Ab1BDFwk convert rfc822-to-8bit (ORCPT ); Fri, 4 Feb 2011 00:52:40 -0500 In-Reply-To: <20110204002043.GA15658@noexit> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Fri, Feb 4, 2011 at 2:20 AM, Joel Becker wrote: > On Fri, Feb 04, 2011 at 12:33:39AM +0200, Amir Goldstein wrote: >> I have been working on porting Next3 snapshots to Ext4 >> with a group of 4 CS students. >> >> This is where it all happens: >> https://github.com/amir73il/ext4-snapshots >> >> Ext4 snapshots prototype is already working! >> Would you like to see a demo? >> >> I would like to present the progress of our work >> and discuss the remaining issues and how they should be best address= ed. >> >> Additionally, I would like to discuss the need for a unified snapsho= ts API that >> would serve both Ext4 and Btrfs. >> This could be useful for someone that wants to implement a generic >> snapshots management system. > > =A0 =A0 =A0 =A0ocfs2 definitely wants to be a part of that discussion= , as we > already do snapshots and thin clones. =A0ocfs2 snapshots are actually= just > thin clones marked readonly. =A0They can be placed anywhere in the > filesystem and are first-class inodes. =A0They do not live in a hidde= n > space like Next3 snapshots seem to. > =A0 =A0 =A0 =A0I've already got a design for a front-end snapshot pro= gram that > implements a policy on top this generic behavior. =A0This design woul= d > cover both first-class and hidden style snapshots, because it assume > snapshots are in a distinct namespace. =A0I haven't gotten around to > implementing it yet, but btrfs and other snapshottable filesystems we= re > part of the design goal. > Cool. I'd love to see a draft (if you already posted it I missed it). I wonder how one deals with different fs with different snapshot capabi= lities, i.e. file level vs. sub/volume level. which one is the case for ocfs2? > Joel > > -- > > "Sometimes one pays most for the things one gets for nothing." > =A0 =A0 =A0 =A0- Albert Einstein > > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0http://www.jlbec.org/ > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0jlbec@evilplan.org > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html