From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: [PATCH v3 00/12] snapshot-merge target
Date: Thu, 19 Nov 2009 09:02:33 -0500
Message-ID: <20091119140233.GA3894@redhat.com>
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Cc: Andi Kleen <andi@firstfloor.org>
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On Thu, Nov 19 2009 at  6:25am -0500,
Andi Kleen <andi@firstfloor.org> wrote:

> Mike Snitzer <snitzer@redhat.com> writes:
> 
> > snapshot-merge target, quilt tree is maintained here:
> > http://people.redhat.com/msnitzer/patches/snapshot-merge/kernel/2.6.33/
> 
> It might seem trivial to you, but afaik nothing in the whole series
> (nor in the comments in the code) says what snapshot merging
> actually is. Please write meaningful changelogs and comments.

OK, I hadn't noticed because I was so focused on the details.

DM (and LVM) snapshot merging allows a snapshot (its COW store) to be
merged back into the snapshot's origin device.

One expected use of snapshot merging is rollback of a root filesystem
after system upgrades (e.g.: yum update).

Mike