[Development] scenegraph performance on the Linux desktop

[Girish Ramakrishnan]

Hi Donald,

On Mon, May 14, 2012 at 5:33 PM, Donald Carr <sirspudd at gmail.com> wrote:
> Guten tag,
>
> I am seeing poor performance of scenegraph on a:
>
> 0f:00.0 VGA compatible controller: NVIDIA Corporation GT200GL [NVIDIA
> Quadro FX 3800] (rev a1)
>
> using the 302.07 driver (Upgraded from 295 in trouble shooting this
> issue). This is clearly using the XCB QPA backend, and does not appear
> to manifest on other lower end GPU hardware I have access to.
>
> I am not using Mesa which is everyone's go to first guess.
>
> I am wondering:
>
> 1) if anyone else is witnessing this
> 2) if people are seeing fantastic performance against the Nvidia
> binary blob, which Nvidia card they are using.
>
> This is a simple example I am seeing this against:
>
> https://github.com/capisce/motionblur
>
> I am seeing around 2-3 fps with kwin composition enabled, around 30
> fps with kwin composition disabled.
> CPU usage of the app is consistently around 4% of a single core
> (according to top)
>
> It would interesting to gather a larger sample set of the afflicted hardware.
>

On my HD 3000 (part of i3 2310M), I get 30fps without run.sh. With
run.sh, I get 60fps. With both of them, many frames are missed and
there is a clear frequent stutter in the animation of the globe. CPU
usage is around 15-20%. resolution for both: 1366x768.

When I decreased the window size to ~1200x700, no stuttering. The CPU
usage is still around 15-20%.

Also, I have seen the stutter in animation in many of the boards. I
don't think it's a graphics issue, something wrong with our timer code
possibly. Is anyone aware of some problem here?

Girish