Re: [Qemu-devel] Re: Spice project is now open

[Dor Laor]

On 12/12/2009 09:48 PM, Izik Eidus wrote:
> On Sat, 12 Dec 2009 13:26:30 -0600
> Anthony Liguori<address@hidden>  wrote:
>
> > Izik Eidus wrote:
> > > On Sat, 12 Dec 2009 11:40:21 -0600
> > > Anthony Liguori<address@hidden>  wrote:
> > >
> > >
> > > > FWIW, I don't see any reason why Spice couldn't be made to be
> > > > separate from guest emulation.  I think it would just require the
> > > > right interfacing in qemu.  I think that's purely an implementation
> > > > detail.
> > >
> > > The QXL device is one of the core compoments of spice..., how can
> > > you separate it from the guest visible state? (it is pci device)
> >
> > How does live migration work then?  Do you have to query libspice for
> > it's state?  Does it return an opaque blob?  How can it integrate
> > with VMState since libspice doesn't have any knowledge of something
> > like VMState?
>
> QXL transfer the device states by itself using qemu migration
> mechanisem.
>
> The spice server just need that the pci memory (and the qxl ram/rom
> state) will be migrate. (From the point of view of guest visible state)
>
> All this guest visible states are transfered by the qxl device using
> qemu.

In addition, the src spice server notifies the client on the migration 
execution and at the end of the migration it commands it to switch to 
the destination. It even passes a one time password session key.

Does vnc has that?

If you're interested of having a basic vnc mode, it will be much more 
easier, cleaner and faster to do the opposite, like Mark suggested -
Add a basic vnc mode to spice.
That said, it shouldn't be a merge criteria, let's start with qxl and 
vdi, and than the spice library.

> > Regards,
> >
> > Anthony Liguori