[mythtv-users] high cpu utilisation with bob deinterlacer

Adam adam at fastmail.com.au
Mon Feb 23 01:40:58 UTC 2009

Jean-Yves Avenard wrote:
> Hi
> 2009/2/23 Tom Dexter <digitalaudiorock at gmail.com>:
>>> I look forward to hearing any suggestions.
>>> _______________________________________________
> Something I've noticed on my set ; is that if the video being played
> match exactly the screen refresh rate ; then X will use 100% of CPU
> usage.
> That's something that has been bugging me for years with the nvidia drivers.
> This stopped happening when using VDPAU
> Jean-Yves
My video card does support vdpau, but I don't want to patch mythtv
manually for vdpau support so I'll just wait until it makes it into the
gentoo package system.

To investigate the cause of the high Xorg usage I disabled VSync in the
X Server XVideo settings and this fixed the problem. Unfortunately
having UseEvents enabled in xorg.conf doesn't help with the matter so
I've just completely disabled vsync for now.

Now with vsync disabled  both cpu cores can scale back to 1200 MHz
during HD playback which means the CPU can run cooler.

I found that I can enable the opengl vsync option in mythtv and this
doesn't cause high  xorg usage but I'm not sure whether it actually
works if you don't use opengl as the render under playback settings. I
did try to test the OpenGL renderer several days ago, but it said the
renderer could not be found (or something similar).
Anyway, I didn't notice tearing with vsync disabled completely so I'll
just live with it for now until vdpau support is included in the ports.

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