[Intel-gfx] Interrupt latency on some 945GM platforms

[Jesse Barnes]

On Thu, 16 Sep 2010 23:06:46 +0300
Vasily Khoruzhick <anarsoul at gmail.com> wrote:

> В сообщении от 16 of September 2010 21:50:50 автор Thomas Gleixner написал:
> > Ok. The problematic part of HPET was not the clocksource, it was the
> > clock event device which failed to deliver interrupts occasionally. It
> > was worth a try at least.
> 
> Hm, it seems that jerky glxgears is not related to jerky keyboard events. 
> Keyboard is jerky only in konsole (kde terminal emulator), it seems something 
> happened it seems that font rendering performance is much worse in latest 
> xf86-video-intel than in xf86-video-intel-2.12.0.

Len just had me try a few things too:
  - maxcpus=1 lets things work
  - offlining cpu1 at runtime (echo 0
    > /sys/devices/system/cpu/cpu1/online) lets things work
  - binding the i915 interrupt to cpu 0 does *not* help

Vasily and Paolo, do you both have Atom CPUs with hyperthreading
enabled?

Thanks,
-- 
Jesse Barnes, Intel Open Source Technology Center