On 11/14/19 10:11 AM, Michael Weiser wrote: > Hello Cole, > > thanks for getting back to me. > > On Tue, Nov 12, 2019 at 12:08:20PM -0500, Cole Robinson wrote: > >>> - create a snapshot of this suspended state including disk and memory >> Since the VM is shutoff, this is actually only snapshotting disk >> contents. So it's no different than snapshotting an offline VM. > [...] >> I assume at this last step, you mean 'revert to the saved snapshot'. So >> the disk contents have been reset to the contents at step 3, and the VM >> is shutoff. But the disk contents at step 3 were essentially the mid >> flight disk contents from the 'save' operation. > > Correct. Sorry for not laying it out more clearly. > >> Yes we need fixes here. Libvirt should be rejecting some of these cases >> I think but virt-manager can help here too. > >> * Run/Revert of a snapshot should be rejected if the VM is in the >> 'Saved' state, aka has been 'virsh managedsave'. This should be done at >> the libvirt level for completeness IMO. Maybe the API needs a flag to >> override this behavior if users know what they are doing > >> * virt-manager prompts to discard saved state first otherwise it doesn't >> all snapshot revert. > >> * Maybe reject snapshot creation when VM is in 'saved' state too, to >> avoid ambiguity, but it's likely not as bad. > > Instead of handling the symptoms, might it be easier to try and make the > saved memory state become part of the snapshot then? I could think of > moving the .save file from the qemu/save into the > qemu/snapshot/<snapshot name> directory. Or resume the saved state into > a running but paused VM and snapshot that so it becomes part of the > snapshot by the native qemu mechanism. > It's possible, but I don't think there will be much energy at the libvirt level to implement or review this. internal snapshots don't get a lot of love as they aren't used by any of the big fancy projects like ovirt or openstack, even at the qemu level they aren't particularly well regarded. - Cole _______________________________________________ virt-tools-list mailing list virt-tools-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/virt-tools-list
