[alsa-devel] alsa-util.c: snd_pcm_avail() returned a value that is exceptionally large: 349696 bytes (1821 ms).

[Raymond Yau]

2009/12/20 Chris <cpollock at embarqmail.com>

> On Sun, 2009-12-20 at 07:47 +0800, Raymond Yau wrote:
> > I can reproduce this bug on pulseaudio-0.9.14 by
> >
> > aplay -v --period-size=32  any_rate_not_equal_44100Hz.wav
> >
> >
> Note - I reported this as bug#
> https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4834 on 14
> December.
>
>
>
http://thread.gmane.org/gmane.linux.alsa.devel/60371

It seem that PA using one or two periods per buffer , the watermark is
alwaysl 20ms for ens1371 for both cases.

when the alsa application (e.g. aplay ) using two periods per buffer , the
buffer are almost 50% full at all time (i.e 175 ms watermark is much higher
than PA glitch mode 's 20ms watermark )

The possibilty of getting underrun is quite high when PA server/PA client
cannot fill the 350 ms buffer in 20ms