CPU usage xorg 7.2 vs current

[Roland Scheidegger]

On 13.03.2009 13:30, Andy Furniss wrote:
> I am not sure whether this is a bug, feature or some build error on my 
> part.
> 
> I've noticed that when playing an unscaled 576*704 25fps test stream 
> with mplayer -vo x11 it is eating way too much CPU with current xorg. I 
> tested git from November and current and am comparing to my base xorg 
> 7.2. The figures below are using the vesa driver, radeon[hd] give 
> similar results.
> 
> CPU is an Athlon 2500 @ 2.1Ghz.
> 
> Xorg 7.2 top shows 75% idle, current git is only 5% idle. In both cases 
> about 12% is mplayer the rest xorg.
> 
> I did a couple of oprofiles below, first is the current xorg.
> 
> The most obvious difference is that the 7.2 version uses libfb.so rather 
> than pixman for some mmx stuff - could this be the reason?

Hmm, shadowfb.
Since the only real difference seems to be that
shadowUpdatePacked uses way more cpu, I've got some doubts. Maybe MTRR
setting failed or something like that?

Roland