Re: FreeBSD CURRENT + DRM + agp_ati

[Adam K K. <ad...@vo...>]

Felix K=C3=BChling wrote:

>Am Donnerstag, den 29.12.2005, 20:40 -0500 schrieb Adam K Kirchhoff:
>[snip]
> =20
>
>>>What's really bizarre, however, is that if I set hw.dri.0.debug to 1,=20
>>>glxgears gets roughly 200 FPS, faster than software Mesa, but slower=20
>>>than it can get (undoubtedly due to the massive amounts of debugging=20
>>>information that the kernel is logging).
>>>
>>>I tried a few more GL programs, all from the xscreensaver package. =20
>>>glforestfire also appear to display less than a frame per second. =20
>>>Same with flip-flop and flyingtoasters.  flurry, on the other hand, is=
=20
>>>quite smooth and the FPS meter shows roughly 30 fps.
>>>
>>>Any ideas?  Thanks!
>>>     =20
>>>
>>So not only does setting the debug sysctl seem to affect the framerate,=
=20
>>so does displaying the framerate within the application.  If I launch=20
>>any of those xscreensaver apps with the -fps option (including flurry,=20
>>glforestfire, flipflop, queens, and flyingtoasters), I get quite=20
>>reasonable framerates.  If I launch them without the -fps option, I get=
=20
>>1 FPS if I'm lucky (and I mean that literally...  The window only=20
>>updates itself once every second, if that).
>>   =20
>>
>
>-fps causes a software fallback which implies a glFinish. Without -fps
>it hits no software fallbacks and interrupt-based frame-throttling will
>be used. Maybe interrupts get lost so that you time-out in the
>frame-throttling code (radeon_wait_irq has a 3-second time-out ATM).
>That would explain low frame rates. With debugging output the waiting
>condition is probably true when it gets to radeon_wait_irq most of the
>time, so it doesn't have to wait -> no time-out. Can you try playing
>with the fthrottle_mode option to test that theory anyway.
>
>  fthrottle_mode=3D0 glxgears
>
>would run glxgears with busy-waiting instead of interrupts.
>
>Regards,
>  Felix
> =20
>

glxgears (and the few other GL apps I've just tried) runs much more like=20
expected with fthrottle_mode set to 0 :-)

Adam