[mythtv-users] Odd video playback behavior

[Jason Ward]

When I watch HD MKV's through MythVideo everything is fine for a few short
minutes.

Then artefact's and stutter appear and this just gets worse until I stop
play back.

This seemed odd to me, both as I have played HD content using other methods
flawlessly, and because of the degregation (although I have no HD tuners so
can't test HD MythTV recorded content).

So I loaded System Monitor and watched what happens.

When the video starts to play CPU usage goes to between 60% and 80%,
outbound network traffic is near zero and inbound jumps up to 4mb and down
to near zero in a stop start fashion.

However, slowly the outbound network traffic builds, eventually reaching a
steady 4mb, at the same time CPU usage creeps up to 90% plus and thats when
the stutter starts.

When I stop playback the outbound traffic falls slowly, taking a minute or
two to fall back to near zero, whereas inbound traffic behaves as expected
and falls to near zero as soon as play back is stopped.

When I watch recording made by MythTV everything works pretty much as
expected, the one thing that does seem a little odd to me is CPU usage
always sits at between 60% and 80% during playback of any kind (i.e. any bit
rate), however outbound traffic does nothing in particular and inbound
traffic arrives in a steady fashion rather than the stop start fashion when
playing through MythVideo.

One difference between the two streams that might have something to do with
this, is that the videos are directly accessible on a mounted share to the
Frontend (in fact the only way I've been able to make it work) whereas the
recorded TV is not and must be stream through backend.

I'm not at all sure what is going off, it's not I'm sure a network problem,
I have a wired 1Gb network throughout.  However, why so much outbound
traffic when playing?  And why the stop start nature of the incoming stream?

My backend is Mythbuntu 0.23 + fixes
My frontend is Ubuntu with MythTV installed from the Mythbuntu website 0.23
+ fixes

Jason
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