On Wed, Aug 11, 2021 at 4:24 PM Arik Hadas <ahadas(a)redhat.com> wrote:
On Wed, Aug 11, 2021 at 2:56 PM Benny Zlotnik <bzlotnik(a)redhat.com> wrote:
>
> > If your vm is temporary and you like to drop the data written while
> > the vm is running, you
> > could use a temporary disk based on the template. This is called a
> > "transient disk" in vdsm.
> >
> > Arik, maybe you remember how transient disks are used in engine?
> > Do we have an API to run a VM once, dropping the changes to the disk
> > done while the VM was running?
>
> I think that's how stateless VMs work
+1
It doesn't work exactly like Nir wrote above - stateless VMs that are
thin-provisioned would have a qcow volume on top of each template's volume and when
they starts, their active volume would be a qcow volume on top of the aforementioned qcow
volume and that active volume will be removed when the VM goes down
But yeah, stateless VMs are intended for such use case
I was referring to transient disks - created in vdsm:
https://github.com/oVirt/vdsm/blob/45903d01e142047093bf844628b5d90df12b6f...
This creates a *local* temporary file using qcow2 format, using the
disk on shared
storage as a backing file.
Maybe this is not used by engine?