Xvideo performance on Radeon 7500 vs Intel 915

[Michel Dänzer]

On Sun, 2006-11-26 at 19:00 -0500, Ken Mandelberg wrote:
> 
> xine with -V xxmc
>    PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
> 32291 km        15   0  223m  46m  28m S 53.6  6.1   0:25.60 xine
>   3954 root      16   0  197m  84m  46m R 28.3 11.1   7:37.75 Xorg
> 
> With xv and xshm there is 0 idle. With xxmc there is about 15% idle, but 
> in all three cases it drops frames (xshm is the worst).

The radeon driver doesn't support XvMC, so this is a little weird.
Probably xine falls back to another output.


> (II) RADEON(0): Will try to use DMA for Xv image transfers

Does Option "DMAForXv" "off" make any difference?


> By the way I'm using your pre-downscale patch to get around the 1536 
> pixel scaling limitation (pink bar). The quality seems ok (at least on 
> the notebook lcd), and I saw the HD performance problem without it.
> 
> Also, I tried moving down to 16 bit depth from 24 and didn't see a 
> difference.

This all makes sense, as the bottleneck is probably the transfer from
system RAM to video RAM. Integrated chipsets actually have an advantage
there.


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