[Spice-devel] Delay in Gimp when using qxl driver

[John A. Sullivan III]

On Wed, 2012-01-18 at 10:44 +0200, Alon Levy wrote:
> On Wed, Jan 18, 2012 at 08:06:40AM +0100, Dominique Rodrigues wrote:
> > Hi,
> > 
> > Since I use qxl driver in virtual desktop powered by qemu-kvm, I
> > found a strange problem with Gimp.
> > 
> > After launching Gimp, open a new windows, and then try to draw
> > something. It appears that the drawing is very slow and does not
> > follow the mouse at all.
> > 
> > It is the same if I use spicy, spicec or vnc to connect to my
> > virtual desktop.
> > 
> > This problem does not appear with cirrus or vmware graphic drivers.
> > 
> > I found that on any Linux distribution (CentOS, RHEL, Scientific
> > Linux, Debian, Ubuntu).
> > 
> > I currently use :
> > - qemu-kvm 1.0 compiled with spice support
> > - spice-protocol 0.10.1
> > - spice 0.10
> > - spice-gtk 0.7
> > - xorg-qxl driver 0.16
> > 
> > Is there any explanation for that ?
> 
> I would assume it is qxl driver cpu bound on something, probably busy
> waiting on the command ring. Can you run perf top on the guest?
<snip>
I believe I had reported a similar issue many months go where just about
any X activity drove our Fedora based CPU through the roof though
Windows was fine.  At the time, I thought you mentioned it was a driver
issue - John