[mythtv-users] Mythtv 0.24 Acer Revo ALSA WriteAudio buffer underruns

[Jean-Yves Avenard]

On 11 February 2011 05:47, John <reidjr at lineone.net> wrote:

> Interesting. I have my front end (Acer Revo) seperate to my backend (Core
> i3) and it seems pause when the backend CPU goes to 100%. In all cases its
> with mysqld when its running one of the scheduling queries. Perhaps when the
> backend CPU is busy the frontends get momentarily starved of data resulting
> in both audio and video buffer underruns. In my last mail I was suggesting
> some query optimisation. I was wondering if there was some temporary
> workaround; e.g increasing (or decreasing) my ALSA or VDPAU buffers. Or
> maybe something with mysqld so that it doesn't lock up the entire machine.
> With a my multi core CPU I'm amazed it does go to 100%. Maybe there's some
> other bottleneck.

I'm intimately convinced that the issue is the communication between
the backend and the frontend.

For all people who mentioned the buffer underruns errors to me; when
using mythavtest on the same file they would get problem on (so the
file is played locally and not streamed from the backend) there are no
issues whatsoever.
Everything plays fine.

Start streaming, either a recording or using the new storage group:
and problems start.

Try this:
if using storage group; mount the recording directory or mythvideos
folder via NFS or cifs ; and play the file using mythavtest
mythavtest -v audio,playback /path/to/file

See if you get any buffer underruns or videos pause during the entire
duration of playback

JY