Re: [Qemu-devel] live snapshot wiki updated

["Daniel P. Berrange" <berrange@redhat.com>]

On Wed, Jul 20, 2011 at 10:26:49AM +0200, Jes Sorensen wrote:
> On 07/19/11 18:47, Daniel P. Berrange wrote:
> > On Tue, Jul 19, 2011 at 04:30:19PM +0200, Jes Sorensen wrote:
> >> On 07/19/11 16:24, Eric Blake wrote:
> >>> Besides, I feel that having a well-documented file format, so that
> >>> independent applications can both parse the same file with the same
> >>> semantics by obeying the file format specification, is a good design goal.
> >>
> >> We all know that documentation is rarely uptodate, new features may not
> >> get added and libvirt will never be able to keep up. The driver for a
> >> file format belongs in QEMU and nowhere else.
> > 
> > This would be possible if QEMU to provide a libblockformat.so library
> > which allowed apps to extract metadata from file formats using a stable
> > API.
> 
> There is no reason for libvirt or any external process to mess about
> with the internals of image files. You have the same problem if the
> image file is encrypted.

Just repeating "libvirt doesn't need todo this" many times doesn't make
it true. I have described why we need to read the disk image to determine
its backing files ahead of QEMU being launched quite clearly.

Daniel
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