[mythtv] XvMC VLD Decoding stuttering problems on some videos

[Isaac Richards]

On Monday 25 September 2006 4:12 pm, Terry Barnaby wrote:
> Hi, a bit stuck now.
> Basically the X11L lock for XvMCPutSlice2 in VideoOutputXv::DrawSlice
> occasionally take a long time to lock (> 300ms). This causes the video
> output stage to run out of decoded video frames and hence a Prebuffering
> pause.
> It looks like the thread holding the lock is doing the XSync in
> VideoOutputXv::Show. However the XSync call never takes longer than a
> few ms and hence should not be holding up the XvMCPutSlice2 for 300ms.
> So, could it be that the display output thread (which is running
> real-time ??) is running hard and not letting the decoder thread get a
> look in occasionally ??

Could be.  Any idea which lock it's waiting on when it's stuck for that long?

Another thing I've been pondering is moving the actual video decode to the 
output thread - keeping the demux separate as it is currently.  Should make 
it possible to get rid of a _lot_ of that locking..

Isaac