Comment 2 for bug 1399191

Revision history for this message
Jeff Cody (jcody) wrote : Re: [Qemu-devel] [Bug 1399191] [NEW] Large VHDX image size

On Wed, Jan 07, 2015 at 03:30:28PM +0000, Stefan Hajnoczi wrote:
> On Thu, Dec 04, 2014 at 01:31:38PM -0000, AMULYA L wrote:
> > Public bug reported:
> >
> > We are trying to convert a VMDK image to VHDX image for deploy to HyperV Server ( SCVMM 2012 SP1) using qemu-img.
> > We tried converting the image using both 'fixed' as well as 'dynamic' format. We found that both the disks occupy the same size of 50GB. When the same is done with VHD image, we found that the dynamic disks are much lesser in size (5 GB) than the fixed disk (50GB).
> >
> > Why is that the VHDX generates large sized images for both the formats?
> >
> > The following commands were used to convert the vmdk image to VHDX
> > format
>
> Jeff, did you fix this recently in commit
> 85b712c9d5b873562c864e72f69cbf0d87d2fe40 ("block: vhdx - set
> .bdrv_has_zero_init to bdrv_has_zero_init_1")?
>
> Stefan

Yes, although there has been a report that there are issues in the
resulting vhdx image in a MS server, after this patch. I am going to
test and fix (if confirmed) once my MSDN subscription is renewed (in
process now, I expect it anytime).

Jeff