EXA performance ( XCOMPOSITE and XRENDER ) performance regression from xorg 7.0 to 7.1 ( r200 )

[James Blanford]

On  2 Jul, Michel Dänzer wrote:
> On Sat, 2006-07-01 at 21:50 -0700, James Blanford wrote:
>> 
>> I'm running a Radeon 8500, also an r200, known to be dog slow with
>> XAA, but seems to be fast with EXA.  It seemed to speed up if
>> anything when I switched to cvs (git?) xserver and drivers.
> 
> Yes, we've been making big improvements since 7.1. I'm using the
> following setup:
> 
>       * xserver git with exa-damagetrack branch merged to my-master
>         branch (based on master) and Option "MigrationHeuristic"
>         "always".
>       * xf86-video-ati git with Option "AccelDFS" (enabled by default
>         with PCI(e), but not AGP) and Option "FBTexPercent" "0".
> 
> This is significantly faster than 7.0 or 7.1 for me with xfwm4's
> built-in compositor, YMMV.

I ran the evas rendering performance test.  Here are the results on my
system with git xserver and ati-driver:

		Fluxbox - No compositing manager

XAA			0.09
EXA - No AccelDFS	2.4
EXA - DFS - SMART	3.7
EXA - DFS - ALWAYS	4.0
EXA - DFS - GREEDY	0.18

		Compiz

EXA - No AccelDFS	2.1
EXA - DFS - SMART	2.0
EXA - DFS - ALWAYS	2.1
EXA - DFS - GREEDY	0.61

The tests ran, but nothing was actually drawn to the screen using XAA
with compiz.  That's like me running a four minute mile by pumping my
legs while sitting in a chair.

So the "greedy" heuristic didn't seem to work well in these tests and
the download from screen hooks didn't seem to help in compiz.  I don't
know what the real world validity is.


>> Compiz is almost unbelievably fast and responsive.  Unfortunately, I
>> get no window decorations.
> 
> Is one of its window decorators running?
> 

Yes, but I also have problems with Kristian's recently posted patches.
Without them, compiz doesn't work at all, but one of them leads to a
null pointer returning from mesa land, so I can't apply it.  When I
search the compiz mailing list and Gentoo and Ubuntu forums, whenever
there's a problem with compiz, people tend to report missing window
decorations.

     -  Jim