From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alasdair G Kergon <agk@redhat.com>
Subject: Re: [Cluster-devel] [Lsf-pc] [LSF/MM ATTEND] [TOPIC] fs/block
	interface discussions
Date: Thu, 11 Dec 2014 00:52:22 +0000
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Cc: Steven Whitehouse <swhiteho@redhat.com>,
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To: Jan Kara <jack@suse.cz>
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On Wed, Dec 10, 2014 at 07:46:51PM +0100, Jan Kara wrote:
>   But still you first need to stop all writes to the filesystem, then do a
> sync, and then allow writing again - which is exactly what freeze does.

And with device-mapper, we were asked to support the taking of snapshots
of multiple volumes simultaneously (e.g. where the application data is
stored across more than one filesystem). Thin dm snapshots can handle
this (the original non-thin ones can't).

Alasdair