[alsa-devel] arecord ..xrun!!!!

[Takashi Iwai]

At Fri, 19 Dec 2008 18:49:04 +0530,
naveenkrishna.ch wrote:
> 
> On Fri, Dec 19, 2008 at 6:34 PM, vasudha rao <vasudha.jrao at gmail.com> wrote:
> 
> > Hi ..
> >
> > I am trying to record .wav files..
> >
> > I did like,
> > $arecord -D copy test.wav
> > Recording WAVE 'test.wav' : Unsigned 8 bit, Rate 8000 Hz, Mono
> > xrun!!! (at least 0.251 ms long)
> > xrun!!! (at least 0.071 ms long)
> > xrun!!! (at least 0.072 ms long)
> > .
> > .
> > .
> >
> > When I run this test.wav, no sound!!!!
> >
> > Am I doing wrong anywhere??
> 
> This print is coming from alsa-utils
> It is all about the underrun and overrun conditions
> 
> I saw some underrun error while playing back
> 
> underrun!!! (at least 771.790 ms long)
> underrun!!! (at least 3393.433 ms long)
> underrun!!! (at least 777.314 ms long)
> 
> 
> Can any one help us understanding the issue, If possible solving it too

Look at the order of measured (least) latency in both cases.
You case is almost 1 second delay while the previous one is less
than 1 ms.  Thus, in your case, it's either really a system latency
such as disk overload or that the buffer DMA isn't properly updated or
set up.

In the previous case, less than 1 ms latency, it implies that the
buffer and period setup is somehow weird.  For example, it's set to
the very small period or buffer size, which can easily result in
buffer underrun.  Check the hw_params constraints and snd_pcm_hardware
setting.


Takashi