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Subject: Re: [Qemu-devel] Re: [PATCH][v2] Align file accesses with
	cache=off (O_DIRECT)
From: Laurent Vivier <Laurent.Vivier@bull.net>
In-Reply-To: <200805202352.17807.paul@codesourcery.com>
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Date: Wed, 21 May 2008 00:59:54 +0200
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To: Paul Brook <paul@codesourcery.com>
Cc: Blue Swirl <blauwirbel@gmail.com>, qemu-devel@nongnu.org, Kevin Wolf <kwolf@suse.de>

Le mardi 20 mai 2008 =C3=A0 23:52 +0100, Paul Brook a =C3=A9crit :
> > When sector-aligned guest offsets are converted to sector-unaligned
> > writes (e.g. due to qcow2 etc.), that property is no longer satisfied=
,
> > and power failure of the host disk can cause more damage than the
> > guest is designed to be resistant to.
>=20
> Seems like the easiest solution would be to have qcow always align its =
writes.
> We don't do on the fly compression, so it should be fairly easy to make=
 this=20
> happen with minimal overhead.

I did the patch you describe and post it to the mailing list on Tue, 22
Jan 2008 11:17:09 +0100, it was called=20
"[PATCH] snapshot=3Don and cache=3Doff compatibility"
but was never commented.

Regards,
Laurent
--=20
------------- Laurent.Vivier@bull.net ---------------
"The best way to predict the future is to invent it."
- Alan Kay