[libvirt] kvm savevm/loadvm

[Chris Lalancette]

On 07/22/10 - 10:40:44AM, Serge Hallyn wrote:
> Quoting Chris Lalancette (clalance at redhat.com):
> > On 07/20/10 - 05:17:43AM, Serge Hallyn wrote:
> > > Hi,
> > > 
> > > virsh has save/restore to do a one-time save+shutdown.  But it
> > > does not expose kvm's savevm/restorevm, which let's me do
> > > incremental snapshots.  Is there a specific reason why that
> > > is not exposed in libvirt, or is it just that noone has
> > > implemented it?
> > 
> > The save/restore API only does a memory snapshot.  If you are referring
> 
> Jinkeys, I guess so - my first tests were confounded by the page
> cache being reverted and then synced back to disk :)
> 
> > to the savevm/loadvm/delvm, which take a disk+memory snapshot, then that is
> > implemented in terms of the libvirt snapshot API.  You can start here:
> > 
> > http://libvirt.org/html/libvirt-libvirt.html#virDomainSnapshotCreateXML
> 
> Ok, so the snapshot created by virDomainSnapshotCreateXML is not what
> is used by 'virsh snapshot-create'?  Are there any plans of exporting
> this through virsh?

No, these two things are the same; virsh snapshot-create calls
virDomainSnapshotCreateXML (which eventually calls savevm in the qemu monitor).

--
Chris Lalancette