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

[Ben Taylor]

On Fri, Dec 11, 2009 at 6:48 PM, Izik Eidus <address@hidden> wrote:
> On Fri, 11 Dec 2009 09:57:48 -0600
> Anthony Liguori <address@hidden> wrote:
>
>> Yaniv Kamay wrote:
>> > Hi,
>> >
>> > Spice project is now open, for more information visit
>> > http://spice-space.org, due to a server relocation the site will be
>> > down during this weekend.
>> >
>> > Spice ship patched QEMU based on fairly old KVM snapshot as a
>> > reference implementation. The Spice team plane to push all the
>> > relevant bits into QEMU upstream.
>> >
>>
>> Historically, we have not supported multiple display mechanisms
>> favoring making one mechanism as good as it can be.
>>
>> Supporting both Spice and VNC would go against this policy.  It's not
>> outside the realm of possibility, but there has to be a good
>> justification for it.
>>
>> We need to separate the advantages of having a paravirtual display
>> driver from the advantages of a remote display protocol.  For
>> instance, VNC is capable of doing ARGB cursor offloading to the
>> client.  We do not support it in QEMU because the VGA drivers we
>> emulate do not support this functionality.  Likewise, VNC can support
>> sound tunneling and QEMU does implement this (although virt-manager
>> does not yet).
>>
>> So from a protocol perspective, what are the advantages of Spice over
>> VNC?
>
>
> Spice desgien is highly diffrence than VNC
> The first thing about spice is that it isnt just a framebuffer drawing
> and not a bitmaps protocol.
>
> Spice protocl support multiple graphics commands, multiple surfaces
> drawings, Spice is desgined to render as less as it can on the server
> and instead to render on the client side much of the work,
> To achive this spice use all kind of techniques such as depth viewing
> tree.
>
> We already have patchs that support offscreen surfaces -> the
> architacture for high end 3d, this make things even more complicated.
>
> Spice is a library, it is library for remote display, it handle by
> itself all the connection between the spice client to the host that run
> the guest, it include:
> sound, display, keyboard, usb, network tunneling (for printers) and so
> on...
>
> The patchs that we wanted to push into qemu were what is called VDI
> interfaces, it allow to qemu work with what ever interface it want,
> what so bad about that?
>
> I think we should allow freedom of choice to the users to decide what
> protcol they want to use, Spice and VNC are all diffrent and were born
> to meet diffrent goals.
>
> I would happy to answer more questions if anyone have

I think the simple point is that, AFAICS, the spice folks are expecting
the qemu team to integrate their big ugly tarball, instead of doing what
everyone else does, which is forward port everything to current head
and then provide a current set of patches against GIT head.

Anything else is just a waste of time. The paths both projects are
at are too far apart.