Bug#668854: nvidia-glx: Upgrade from 295.33 to 295.40 causes serious performance regression

[Witold Baryluk]

On 04-15 10:54, Andreas Beckmann wrote:
> On 2012-04-15 03:15, Witold Baryluk wrote:
> > Updated and now, glxgears gives me something around 5 or 6 fps (previously
> > 60+),
> > wine games which had easly 50 fps, now had 2, and have serious drawing delay,
> > even in 2D mode.
> 
> OK, lets see if the problem is caused by teh security fix by applying 
> it to 295.33:
> 
> Downgrade to 295.33-1 from testing and verify that it still works as
> you would expect.
> 
> # remove previously built module
> dkms remove nvidia/295.33 --all
> 
> # download the patch and apply it to the sources
> wget ftp://download.nvidia.com/XFree86/patches/security/CVE-2012-0946/nvidia-blacklist-register-mapping-290-295.diff -O - | patch -p1 -d /usr/src/nvidia-295.33/
> 
> # rebuild module
> dpkg-reconfigure nvidia-kernel-dkms
> 
> Thereafter reboot (or ensure otherwise that the new module gets loaded)
> and check performance.
> 
> To go back to the original (unpatched) 295.33 driver you can run
> apt-get install --reinstall nvidia-kernel-dkms=295.33-1
> and reboot afterwards.
> 
> After this test, please report your issue to NVIDIA, following their 
> bug reporting instructions:
> http://www.nvnews.net/vbulletin/showthread.php?t=46678
> (This should be done while running 295.40)
> Include the result of the above test: "295.33 with the security fix
> applied does/doesn't show this behavior"
> And of course report your findings and a link to a corresponding thread
> in the Nvidia forum to this Debian bug report.
> 
> Andreas

Thanks for instructions!

For future reference:

295.33  - no problems (full performance)
295.33 + nvidia-blacklist-register-mapping-290-295.diff - no problems (full performance)
295.40 - regression (drastict performance loss)


(by drastic I mean, from 1400 fps to 5 fps in glxgears, or from 50 fps
to 0.5 fps in Counter-Strike 1.6 under wine).


Reported as http://www.nvnews.net/vbulletin/showthread.php?p=2546075

Regards,
Witek

-- 
Witold Baryluk