i915 driver slowdown after 1-2 days?

[Chun-Yu Shei <cshei@cs.indiana.edu>]

Hi,

I'm currently running xf86-video-intel 2.13.0 with an i5-540M, and I've 
been experiencing a strange issue where after a day or two, I can no 
longer play videos smoothly in Flash 10.2 beta, as well as in VMWare. 
Even moving windows in VMWare guests becomes slow and visibly laggy. 
It's almost as if there's no video acceleration -- the frame rate drops 
drastically, and CPU usage seems to increase significantly.  Playing 
video in mplayer still works perfectly, however.  Restarting X has no 
effect, and I have to do a full reboot to get rid of the problem.  I'm 
running 64-bit Gentoo with the following:

libdrm 2.4.22
mesa 7.8.2
2.6.36 kernel
xorg-server 1.7.7

The problem also occurs with the 2.6.35 kernel, and I've also been able 
to replicate it in a fresh install of Ubuntu 10.10.  There are no 
indications of any problems in both the output of dmesg and the Xorg 
logs, and the output of intel_gpu_top looks no different before/after 
the problem occues.  I'm on a ThinkPad X201 with an external display 
connected via DisplayPort, and I do suspend it with the hibernate-ram 
script.  Is this a known problem by any chance?  If not, how might I go 
about troubleshooting this?

Thanks,
Chun-Yu