From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joel Becker <Joel.Becker@oracle.com>
Subject: Re: [PATCH 1/3] fs: Document the reflink(2) system
	call.
Date: Tue, 5 May 2009 15:21:31 -0700
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Cc: Theodore Tso <tytso@mit.edu>, jmorris@namei.org,
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        jim owens <jowens@hp.com>, Chris Mason <chris.mason@oracle.com>,
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To: Jamie Lokier <jamie@shareable.org>
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On Tue, May 05, 2009 at 11:12:36PM +0100, Jamie Lokier wrote:
> Joel Becker wrote:
> > 	The point-in-time of the snapshot is what's important here.
> 
> Don't we have a slight problem that useful point-in-time snapshots
> really need to snapshot whole directory trees?  Otherwise you get the
> same inter-file inconsistency issues that you get intra-file from old
> fashioned copying.

	Snapshotting whole trees is already doable from things like
btrfs and from whole volumes on your storage.  This is a different
beast.
	Inter-file is a lot easier to handle than intra-file, because
you have control over that part of the process.
	And if your file is actually a disk image, you get snapping of
disks for free :-)

Joel

-- 

"We'd better get back, `cause it'll be dark soon,
 and they mostly come at night.  Mostly."

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127