nvidia X driver and OpenGL performance problem

[Hans Nieser]

Hans Nieser wrote:
> Hans Nieser wrote:
> 
>> Hi list,
>>
>> Recently I've been trying out games such as the Doom 3 demo (Linux 
>> binaries), Quake 2, Quake 3 Demo (Linux binaries) and the new Quake 4 
>> port (also Linux binaries) under FreeBSD, and although they run 
>> without any errors or visual oddities, the performance has been 
>> somewhat dissappointing - they all run about 3 to 4 times slower than 
>> they do on Windows and are hardly playable (except for Quake 3 / 2, 
>> but those obviously require much less of the video hardware). This 
>> seems to be the case with all OpenGL games / apps. glxgears with its 
>> default settings (that is, I just typed 'glxgears' with no options) 
>> renders about 7200 FPS on average.
> 
> Well here's an interesting twist; when I log into X/Gnome as root, the 
> games run a heck of a lot smoother (note that su/sudo doesn't have the 
> same effect, I really have to login as root). Quake 4 went from 10-20 
> fps in the first level to 40-50 fps on average.
> 
> I'm guesssing however that playing games as root (online games, that is) 
> might not be a good idea. Now I just need to figure out what exactly 
> makes games run slower for non-root users.

To continue my monologue, it seems I was either mistaken about improved
performance when running OpenGL apps as root (I guess I should start doing
real benchmarks), or it was some kind of fluke as I have been unable to
reproduce it.

I've been told by an individual in #nvidia on freenode IRC that PCI
Express cards run at the speed of the normal PCI bus in FreeBSD because it
doesn't have complete support for PCI Express yet, and conseuently,
neither does the nvidia FreeBSD driver.

Although this would certainly explain my troubles, after numerous searches 
on google on FreeBSD and PCI Express I have been unable to confirm the 
above. Could anyone shed some light on this? Should I give up trying to 
get my OpenGL apps to perform like they should as PCI Express is simply 
not fully supported (yet)?