pulseaudio and kvm...

[Matthew Gillen]

Stephen Adler wrote:
> Guys,
> 
> It seems that when I play a utube video clip in my web browser, my kvm 
> virtual machine looses the ability to play sound. I have to shutdown 
> firefox, before the virtual machine will then play sound. I was 
> wondering if the kvm virtual machines are configured to use alsa or 
> pulse audio? Or do they grab the audio device directly?

The whole point of ALSA was to get rid of the notion that only a single pid
could write to the sound device.  Even if your adobe-flash plugin (playing
youtube) uses the OSS interface, the current "OSS" drivers are emulated by
ALSA.  So if you're using ALSA drivers (and you'd have to make some extra
effort to not use them, since AFAIK they're the default for all hardware now),
there shouldn't be an issue like you're describing.

It sounds like a buggy ALSA driver if it allows one pid to prevent other pids
from writing to the device.

All the ALSA drivers are pre-pended by 'snd'.  If you do an 'lsmod', you
should see a bunch of
 snd-*-oss
lines.  What's your lsmod output look like, or better yet, what does the diff
of before and after you watch a youtube video (but before you close firefox)
look like?


Matt