From: Joe Thornber <thornber@redhat.com>
Subject: Re: [PATCH v1 00/30] Ext4 snapshots
Date: Mon, 13 Jun 2011 14:50:07 +0100
Message-ID: <20110613135007.GC3049@ubuntu>
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Cc: sandeen@redhat.com, tytso@mit.edu, snitzer@redhat.com,
        Yongqiang Yang <xiaoqiangnk@gmail.com>, lvm-devel@redhat.com,
        Lukas Czerner <lczerner@redhat.com>, linux-ext4@vger.kernel.org
To: "Amir G." <amir73il@users.sourceforge.net>
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On Mon, Jun 13, 2011 at 04:26:16PM +0300, Amir G. wrote:
> with ext4, snapshots reads may cause extra seeks, but main fs will
> stay optimized for reads.
> with thinp and multisnap, there is no optimization for read from one
> specific target, but I admit that can change in the future when auto defrag
> heuristics are applies to multisnap.

I'm going to keep things symmetrical. A lot of use cases involve
pointing at an arbitrary snapshot and saying "that's now my master".
This is connected to why I support arbitrary depth of recursive
snapshots too.

- Joe

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