[Mplayer-advusers] Bug? Anomalous CPU usage when playing HDTV clips.

[John Stebbins]

Ivan, I couldn't find an easy way to disable VSync in the X 
drivers. I'm not even sure all the configurations I tried this
on have VSync capability.

I'm not sure what you are referring to with regard to checking
AGP tuning/speed.  All systems tested are AGP 4x.

I have been running some additional experiments that may shed some
more light on the problem.  I would say that this is some problem
with X alone, but look at the last test that I run below.  There is
some very odd interaction that involves image size, fps, and
X extensions being used that also affect mplayers cpu usage.

Here's an interesting one.  Double buffering extension(dbe) 
seems to have some odd effects.

I ran a series of tests using:
1280x720 @ 30fps clip
1024x576 @ 30fps clip
xv output
x11 output
dbe enabled
dbe disabled

Results
-------
                         X CPU         mplayer CPU
1280x720,xv,dbe          30            30

1280x720,x11,dbe         30            30

1280x720,xv,no-dbe       30            30

1280x720,x11,no-dbe      negligible    30

1024x576,xv,dbe          negligible    30 (you would think mplayer CPU
                                           should have dropped here by
                                           50% due to smaller image size)
1024x576,x11,dbe         negligible    30

1024x576,xv,no-dbe       negligible    30

1024x576,x11,no-dbe      negligible    5-20 (mostly under 10) HUH!?


>I've just got another (simplier) idea.
>It could also be connected with VSync (changing picture
>on retrace). You can test this by increaseing monitor
>vertical refresh rate. Or finding option to disable
>VSync.
>
>--- Ivan Kalvatchev <iive at yahoo.com> wrote:
>> Hmm quite interesting.
>> My quess is that the you may have reached AGP limit.
>> Could you check your AGP tunning/speed?
>> Best Regards
>   Ivan Kalvachev
>  iive