[mythtv] Mythmusic hangs

[Colin Guthrie]

Hi,

Miah Gregory wrote:
> Hi,
> 
> Running from week old SVN (planning to upgrade tonight).
> 
> I've had a search of the various mailing lists and asked on IRC, but
> no-one's seen this problem before, so I'd like some help in debugging
> it. Basically the problem is that when you switch tracks in mythmusic,
> either manually whilst one is playing, or automatically as each track
> ends, there's around a 10 second delay during which the front end is
> unresponsive, cpu load is fairly minimal, and if a track was playing at
> the time, around half a second of audio loops constantly for around 10
> seconds. After this delay, the next track starts successfully.
> 
> I straced the process and believe that mythmusic was hanging whilst
> closing the filehandle to /dev/dsp - has anyone seen this before? My
> suspicion is that the audio code isn't closing down /dev/dsp properly,
> eg. unmapping buffers or whatever, and hence the close() hangs to allow
> the buffers to all empty or something?
> 
> Very occasionally, mythmusic has crashed whilst attempting the track
> change, but I've been so far unable to reproduce this in a debugger.
> 
> Any help to continue debugging would be appreciated (on irc as mace if
> that's more convenient).


I'm fairly out of touch with the mythmusic code since I've not been 
hacking on it for a while now.

There is not reason (that I can think of) as to shy MythMusic /should/ 
be closing down /dev/dsp on a track change. We only need to flush our 
own buffer and then pipe in new data. Unless there is soem sort of 
sample rate change this shouldn't be a problem.

Have you tried using both OSS and Alsa output?

Personally, I've never seen this behaviour myself, so if you can work 
out how to reliably reporoduce it it would be a bonus.

Col.
-- 

+------------------------+
|     Colin Guthrie      |
+------------------------+
| myth(at)colin.guthr.ie |
| http://colin.guthr.ie/ |
+------------------------+