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Subject: Re: [linux-lvm] Snapshot question...
From: "Brian J. Murrell" <brian@interlinx.bc.ca>
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Date: Tue, 22 Apr 2008 12:12:14 -0400
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On Tue, 2008-04-22 at 11:47 +0100, Stephane Chazelas wrote:
>=20
> but
> when you write to it, the system makes sure that unless it has
> been done already, the block you're modifying are being copied
> first from the "real" volume to COW volume before being modified
> in the "real" volume.

And to be clear, the COW volumes of _all_ snapshots[1].  This is where
the snapshot scaling problem arises.

Zumastor claim to have solved that with their snapshots.  I'd love to
have time to play with it, indeed.

If Zumastor are here listening, can you answer, are there any plans to
get your snapshots into the main kernel tree?

b.


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