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Date: Tue, 12 Aug 2014 19:39:22 +0100
From: "Richard W.M. Jones" <rjones@redhat.com>
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Subject: Re: [Qemu-devel] disk image: self-organized format or raw file
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To: Eric Blake <eblake@redhat.com>
Cc: =?utf-8?B?5ZC05YW05Y2a?= <wuxb45@gmail.com>, qemu-devel@nongnu.org, Kirill Batuzov <batuzovk@ispras.ru>

On Tue, Aug 12, 2014 at 08:07:55AM -0600, Eric Blake wrote:
> On 08/12/2014 07:45 AM, =E5=90=B4=E5=85=B4=E5=8D=9A wrote:
>=20
> [please don't top-post on technical lists]
>=20
> > Thanks for your information. It's really helpful.
> > I think adding a bitmap alongside the raw file ( or just within that =
file)
>=20
> Umm, how do you propose to add a bitmap within a raw file?  The moment
> the file contains metadata, it is no longer raw, but some other format.
>  You'd need a way to reliably delineate the portion of the file that
> contains the bitmap and therefore must not be exposed to the guest.

There was an MSFT format where they used raw but added metadata after
the end of the raw file data.

https://en.wikipedia.org/wiki/VHD_%28file_format%29

This is crazy BTW - I'm not advocating we do it :-)

Rich.

--=20
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rj=
ones
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