Very low fps with Mesa 6.5.3 and 7.0.1 with Matrox G450 card

[Oleg <xs...@ma...>]

I just upgraded my Mesa package from 6.5.2 to 7.0.1 version and check if it 
fix bug noted here: http://bugs.freedesktop.org/show_bug.cgi?id=9969

And i was wondered how low fps i have in sauerbraten game (at all maps). To 
compare fps i has choosed some place at some map which i bring to just after 
map load and got next results (i also add here results which i got later, 
when testing 6.5.3):
6.5.2                           23fps
6.5.2 (recompiled)        25fps
6.5.3                           9fps
7.0.1                           9fps

It's very much, game is completely unplayable :-(

I'm sure that i has installed mesa 7.0.1 correctly: i've checked that all 
libraries (libGL, libGLU, libglut, libGLw), binaries (glxinfo, glxgears, 
etc), drivers (mga_dri.so) were really updated and there is no old ones. 
Right after X start i has checked glxinfo's OpenGL version string, it sad 
that i use Mesa 7.0.1 DRI module and that direct rendering is enabled.

Next step i tried was to compare (diff -urN) 
Mesa-7.0.1/src/mesa/drivers/dri/mga/ with same dir at Mesa-6.5.2 and i not 
note any significant changes.

Then i've tried to replace mga_dri.so from 7.0.1 to mga_dri.so from 6.5.2 
(provided with my Linux distributive). And i see that glxinfo's OpenGL 
version string shows me Mesa 6.5.2. Checked fps and voila 23fps, as before 
was (but bug, mentioned in beginning of this message was present).

Next steps were to check if my compile environment is bad, so i've recompiled 
Mesa 6.5.2 from source with default linux-dri-x86 config (i.e. i've not added 
any CFLAGS= or changed any files in any dir at source tree) and again replace 
only mga_dri.so with new, just compiled variant. Nothing changed, i've got 
good 23fps.

I also tried to compile and replace mga_dri.so with compiled by me 6.5.3 
version of Mesa, and i got bad 9fps :-( I can't play long time sauerbraten 
with 6.5.3 or 7.0.1 version as it was slow, but i've not got bug mentioned at 
top of this message.

I also tried to use drm kernel module from git (drm 1.1.0 20060810/mga 3.2.2 
20060319), but it not help to improve perfomance with Mesa 6.5.3 or 7.0.1.

System info:
AMD Athlon 850
VIA KT133
Matrox G450 32Mb DDR
Linux Slackware 12.0
Kernel 2.6.22.1 (myself compiled)
Xorg 1.3.0 (provided by distribution)

I use startx command to run X server, so there is no strange things produced 
by not restarted X with xdm/gdm/kdm.

What can i do to improve perfomance with Mesa 6.5.3/7.0.1? Is it planned to 
improve it (already checked TODO list)? :-\

P.S. This is crosspost from xo...@li... , it was recommended at 
xorg list by Roland Scheidegger, his answer is here:
> Indeed a hefty performance drop. You could try figuring out if the time 
> is spent somewhere in the driver with oprofile (as opposed for the 
> driver just waiting for the gpu), it might give a hint why it's so much 
> slower.
> btw you'd better bring this up on dri-devel.
I'm not familiar with oprofile tool and not professional programmer :-\
If someone may explain generic commands to debug/profile (if it's required), 
then i may try to do my best.

-- 
Best regards, Oleg