radeon with DRI2 slower?
I noticed that switching DRI2 on with radeon (R500) is considerable slower than using DRI1. Furthermore all application and games seem to be locked at 30fps.
Is there perhaps some VSYNC forced on by default or is the new memory menager still not mature?
Considering that the radeon KMS is still in the staging area of an unreleased kernel, that seems not far-fetched.
dri2 currently is only available for cards until the r5xx, right ?
I'd really like to use it with my 4850 if it wasn't too buggy (meaning extremely unstable or hardlocking my box)
these graphical corruptions with compiz are driving me nuts
kernelOfTruth, you are one lucky guy to be in Vienna. I'd give my eye teeth to live there... even though I cannot abide Sachertorte.
Seat of the pants DRI2/KMS actually feels faster to me and I'm no longer having an issues with X crashing while running Compiz. Very stable.
1st gen Macbook Pro with X1600
Week old Mesa, DRM and xf86-video-ati git pull.
DRI2 is mostly only supposed to be faster if you're running OpenGL under OpenGL compositing (eg Compiz). DRI2 without compositing is slower than DRI1 without compositing afaik. ^^
Reason being with DRI2 you can get direct rendering under Compiz.
Now that I read that again, I'm actually less sure. That smells very much like vsync if you get that even with simple OpenGL games...
Originally Posted by madman2k
If even the non-benchmark glxgears runs at 30fps, it's likely either something related to vsync, or maybe some parts of your stack aren't being hardware accelerated after all (check glxinfo).
If you're certain that neither of the above is the case, then it's a bug. (Actually, even if vsync is to 30fps, that should still be considered a performance problem since we really want vsync to monitor refresh rate...)
That would follow as I haven't played a game in three years. Sad state of affairs...
Originally Posted by nanonyme
thanks for the hint. glxgears runs at ~1000fps. After that I tried changing my refresh rate from 60hz to 50hz and voila: chromium ran at 50fps (most of the time). So it seems to be a combination of vsync and driver slowness. When the rendering is to slow to produce 60fps it drops to a integral divider which is 30fps because of vsync. But it seems it still can produce 50fps constantly.
Originally Posted by nhaehnle
Is there a way to disable vsync with DRI2? I am using the Xorg edgers PPA, so everything is just several days old...
Well, that's only for doing the same things DRI1 is capable of. You get more extensions (and higher level OpenGL) supported with KMS+mm and might end up getting better performance in complex applications later on (read: games).
Originally Posted by amphigory
Tags for this Thread