Bug#617624: xserver-xorg-video-radeon: serious performance regression with 6.14 versions of driver and R480 chip (X850 XT)

[Michel Dänzer]

On Don, 2011-03-10 at 13:27 +0000, Mike Brodbelt wrote: 
> * Michel Dänzer <daenzer at debian.org> [110310 08:27]:
> > 
> > > The poor performance is also causing perceptible flicker in terminals
> > > while typing.
> > 
> > Which terminal emulator application is that with?
> 
> Eterm - though I'm of the opinion that the terminal emulator isn't
> actually relevant.

Well, if it uses core X11 fonts, then text is rendered in software,
which could certainly explain at least some of the issues. If you're
using a non-anti-aliased font in the terminal, does switching to an
anti-aliased one improve terminal performance?


> The problem appears to be affecting any application that moves
> substantial amounts of graphics data around - so scrolling a
> large amount of text in a terminal window causes visible flicker.
> Equally, rapidly moving a window around the desktop causes very
> obvious lag as the X server struggles to keep up, with ghost images
> being left around for a short period afterwards. 

I'm afraid that's rather vague and doesn't ring any bells.


> This happened after a dist-upgrade, so something ha clearly regressed
> pretty severaly with my configuration. I've tried with the xorg.conf
> in place, and also without any xorg.conf at all with the same results.
> I've also tried with 2.6.32 and 2.6.37 kernels.

Then I don't suppose Option "ColorTiling" "off" helps, as I don't think
that could have been enabled with 2.6.32.

Basically, you need to try and narrow down further what exactly made
things worse for you. Is it the new X server or driver? ...

Though, if the bad performance is accompanied by high CPU usage of the X
server process, getting a profile with sysprof or oprofile might give an
idea of what's going wrong. Please make sure the xserver-xorg-core-dbg
and xserver-xorg-video-radeon-dbg packages are installed for this.


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer