Bug#620858: slow performance continues

[Alex Deucher]

On Mon, Apr 4, 2011 at 8:01 PM, Andres Cimmarusti <acimmarusti at gmail.com> wrote:
> Package: xserver-xorg-video-radeon
> Version: 1:6.14.0-1
> Followup-For: Bug #620858
>
> I set vblank_mode=0 using a .drirc file in my home directory. This
> caused the overall slow down I was only experiencing after resuming from
> suspend to manifest itself all the time. Framerate in glxgears was no
> longer in sync with refresh rate, but it was quite poor (<200 fps). In
> the past I've gotten more like 800 fps (radeon) and 1200 (catalyst on
> lenny). Also, only by moving the cursor with the touchpad, causes the
> framerate in glxgears to drop further.

gears is not a benchmark.  It's highly CPU dependant.

>
> Desktop experience is quite slow. I pulled mesa 7.10.1 from experimental
> to see if this would help, but it didn't. The good news is that, after
> waking from suspend graphics performance is the same.
>
> Also I would like to correct a statement I made on my first email.
> Restarting X does not fix the problem (when vblank_mode is NOT set to
> zero).
>
> $ glxinfo | grep renderer
> OpenGL renderer string: Gallium 0.4 on ATI RS480
>

Since you are using gallium make sure it is built with llvm support as
that is very important for asics without vertex hardware.  You can
also disable tear-free buffer swaps by adding:
Option "SwapbuffersWait" "FALSE"
to the device section of your xorg.conf.  That coupled with
vblank_mode=0 should give you maximum framerates at the expense of
tearing.

Alex