[Engine-devel] [vdsm] Multiple graphics framebuffers - VDSM support

[Michal Skrivanek]

On Nov 26, 2013, at 15:57 , Frantisek Kobzik <fkobzik at redhat.com> wrote:

> Hi guys,
> 
> I created a wiki page with the feature: http://www.ovirt.org/Features/Multiple_Consoles
> 
> It contains information about possible redesign of Engine<->VDSM communication.
> I'd appreciate if you take a look at it since it's not trivial change. 
> 
> I welcome opinions from both engine and vdsm devels.

I think we indeed have to split video device from graphics device and treat it separately…

Thanks,
michal

> 
> Cheers,
> F.
> 
> ----- Original Message -----
> From: "Frantisek Kobzik" <fkobzik at redhat.com>
> To: vdsm-devel at lists.fedorahosted.org
> Sent: Monday, November 25, 2013 2:23:59 PM
> Subject: Re: [vdsm] Multiple graphics framebuffers - VDSM support
> 
> Hi,
> 
> it's been some time since the original mail, so I'm sending updated information.
> 
> 
> ----- Original Message -----
> From: "Frantisek Kobzik" <fkobzik at redhat.com>
> To: vdsm-devel at lists.fedorahosted.org
> Sent: Thursday, November 7, 2013 11:47:46 AM
> Subject: [vdsm] Multiple graphics framebuffers - VDSM support
> 
> Dear VDSM developers,
> 
> I'm working on a patch that allows running a VM with multiple graphics framebuffers. This is handy when you want to run a VM with both SPICE and VNC. It's a 3.4 feature and it will certainly need a change in vdsm.
> Here is a list of changes in VDSM that are needed for this funcionality:
> a, Sending graphics/video (engine->vdsm)
> - currently we send two things:
>  1, "display" value (qxl/vnc [wat])
>    - vdsm uses this for determining if the graphics server is SPICE or VNC
>    - this attribute is not really correct - it mixes up semantics of graphic
>      framebuffer and videocard together. I believe this attribute should only
>      contain information about the graphics ('spice', 'vnc' or 'spice,vnc' if
>      you want both). if this the case, do you think we should rename the attribute
>      to, let's say, 'graphics'? Is it even possible with regard to backward 
>      compatibility? or should I reuse 'display' attribute?
>  2, video device (json representation of the video card) - this is correct
> 
> b, Reporting graphics ports (vdsm->engine)
> - currently we report 2 graphic ports ('displayPort' and 'secureDisplayPort')
> - if we want multiple framebuffers, we must report more ports (for VNC and 
>   SPICE together that would mean 3 ports (2 for spice, one for vnc).
> - there are two possible solutions for this:
>  1, ditch 'displayPort' and 'secureDisplayPort' and add new 'spicePort',
>     'spiceSecurePort', 'vncPort' fields or some kind of two level dict:
>        { protocol -> secured/unsecured -> portNumber }
>  2, keep 'displayPort' and 'secureDisplayPort' and introduce new 'additionalDisplayPort'
>     This would be friendlier to backward compatibility, but it's extremely
>     ugly because of unclear semantics of the fields (in case of SPICE+VNC
>     'displayPort' and 'secureDisplayPort' would be related to SPICE, 
>    'additionalDisplayPort' would be the VNC port. In case of VNC only, the 
>    'displayPort' would be suddendly VNC port... ewww).
> 
> I'd be very happy if you share your opinion about these changes.
> 
> Cheers,
> Franta.
> _______________________________________________
> vdsm-devel mailing list
> vdsm-devel at lists.fedorahosted.org
> https://lists.fedorahosted.org/mailman/listinfo/vdsm-devel
> _______________________________________________
> vdsm-devel mailing list
> vdsm-devel at lists.fedorahosted.org
> https://lists.fedorahosted.org/mailman/listinfo/vdsm-devel