[libvirt-users] Reintroduce "allocate entire disk" checkbox on virt-manager

[Cole Robinson]

On 06/18/2018 04:05 PM, Gionatan Danti wrote:
> Hi list,
> on older virt-manager versions (ie: what shipped with RHEL 6), a
> checkbox called "allocate entire disk" was selectable when configuring a
> new virtual machine. When checked, it means that the RAW disk image file
> was entirely allocated, generally issuing a fallocate() call. When
> unchecked, the disk image was a sparse file, with on-demand space
> allocation.
> 
> On new virt-manager versions (ie: what ships with RHEL 7), the checkbox
> is gone. This means that for creating a sparse allocated file from
> within the "new vm" wizard, one is forced to use a Qcow2 file
> (selectable in the global preferences). No sparse RAM images can be
> created within such wizard.
> 
> As a heavy consumer of RAW disk files, I would really like to have the
> checkbox back, especially in RHEL/CentOS 7.x
> Do you plan to reintroduce it? For RHEL/CentOS, should I open a Bugzilla
> ticket?

If you change the disk image format from qcow2 to raw in
Edit->Preferences, then new disk images are set to fully allocated raw.
Check the image details with 'qemu-img info $filename' to confirm. So I
think by default we are doing what you want?

- Cole