[mythtv-users] Exiting playback is very slow

Jim Stichnoth stichnot at gmail.com
Wed Nov 18 18:39:14 UTC 2009

On Thu, Nov 12, 2009 at 11:30 AM, Daniel Kristjansson
<danielk at cuymedia.net> wrote:
> On Wed, 2009-11-11 at 20:33 -0800, Jim Stichnoth wrote:
>> So if I want to improve the stop-playback performance, it seems I have
>> two choices.  First, I could try reducing the number of VDPAU buffers.
>>  What is special about 17 buffers?  Are there any guidelines on how
>> many are necessary for a given recording?
> You might want to post your analysis to mythtv-dev, maybe Isaac or Mark
> will have some ideas on how to speed this up. It would be nice to make
> this faster before 0.23. VDPAU also slows down the startup of video
> playback, but we're not quite sure why yet.
> -- Daniel

I forgot to follow up on this.  I tried freeing the buffers in a
separate thread, but then the logs showed "VDPAU display preempted"
messages, so this may not be a viable approach.  Perhaps nVidia will
just improve the performance of buffer deallocation in a later
release.  Also, the approach mentioned several times here -- having
myth figure out the minimum number of buffers for a given recording --
should help a lot, at least for me.  I found that the minimum of 6
buffers is sufficient for my ATSC recordings as well as 720p HDPVR
recordings.  I needed more buffers for movies taken on my Canon
PowerShot camera, and that magic value of 17 was needed for one of my
files that I think originated from BBC.


More information about the mythtv-users mailing list