Strange slowdown with new Matrox driver(XFreee)

SDL Development
1

Hello everyone!

Recently I have upgraded my system from SuSE 8.1 to 8.2 which has SDL
version 1.2.5. I am not sure what version of SDL I was using before, but X
was 4.2.0 vs. 4.3.0 now. The problem is the following:

My 2d games are running very slow when using mga (G550) driver. With
windowed 800x600x16 bit I get around 24fps (100% CPU usage) which is twice
as slow as before when I was getting 50fps (target fps) with 60-70% CPU
usage.

I tried a simple test and got X working with fbdev driver. To my suprise,
everything was back to normal ie. working fast! Plain vesa driver is also
much faster than mga?!

I don’t know if the problem is mga driver or something else. I think the
code is ok because it worked fine before and all surfaces are converted to
display format before blitting.

You can look at the code under project hungry-bear at sourceforge.net.

Any hints are greatly appreciated!

2

Hello everyone!

Recently I have upgraded my system from SuSE 8.1 to 8.2 which has SDL
version 1.2.5. I am not sure what version of SDL I was using before, but X
was 4.2.0 vs. 4.3.0 now. The problem is the following:

My 2d games are running very slow when using mga (G550) driver. With
windowed 800x600x16 bit I get around 24fps (100% CPU usage) which is twice
as slow as before when I was getting 50fps (target fps) with 60-70% CPU
usage.

I tried a simple test and got X working with fbdev driver. To my suprise,
everything was back to normal ie. working fast! Plain vesa driver is also
much faster than mga?!

I suspect there’s a bug in the 4.3.0 X server that’s causing the slowdown.
You might try posting on the XFree86 development lists and see if they have
any suggestions…

See ya,
-Sam Lantinga, Software Engineer, Blizzard Entertainment

3

— Sam Lantinga wrote:

Hello everyone!

Recently I have upgraded my system from SuSE 8.1
to 8.2 which has SDL
version 1.2.5. I am not sure what version of SDL I
was using before, but X
was 4.2.0 vs. 4.3.0 now. The problem is the
following:

My 2d games are running very slow when using mga
(G550) driver. With
windowed 800x600x16 bit I get around 24fps (100%
CPU usage) which is twice
as slow as before when I was getting 50fps (target
fps) with 60-70% CPU
usage.

I tried a simple test and got X working with fbdev
driver. To my suprise,
everything was back to normal ie. working fast!
Plain vesa driver is also
much faster than mga?!

I suspect there’s a bug in the 4.3.0 X server that’s
causing the slowdown.
You might try posting on the XFree86 development
lists and see if they have
any suggestions…

See ya,
-Sam Lantinga, Software Engineer, Blizzard
Entertainment

I’m no pro on this, but prehaps you had DRI enabled
before and the new driver dosn’t?__________________________________
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4

Sam Lantinga wrote:

Recently I have upgraded my system from SuSE 8.1 to 8.2 which has SDL
version 1.2.5. I am not sure what version of SDL I was using before, but
X was 4.2.0 vs. 4.3.0 now. The problem is the following:

My 2d games are running very slow when using mga (G550) driver. With
windowed 800x600x16 bit I get around 24fps (100% CPU usage) which is
twice as slow as before when I was getting 50fps (target fps) with 60-70%
CPU usage.

I tried a simple test and got X working with fbdev driver. To my suprise,
everything was back to normal ie. working fast! Plain vesa driver is also
much faster than mga?!

I suspect there’s a bug in the 4.3.0 X server that’s causing the slowdown.
You might try posting on the XFree86 development lists and see if they
have any suggestions…

Yep, it was definately a bug in XFree 4.3.0. I have upgraded some rpm
packages for my distro and the problem went away.

Thanks!