[LAD] ALSA latency and MMAP

[Clemens Ladisch]

Paul Davis wrote:
> On Mon, Sep 7, 2009 at 4:53 AM, Clemens Ladisch<clemens at ladisch.de> wrote:
> > There is no extra buffer for these functions; snd_pcm_write/read* copy
> > the data to/from the same hardware buffer that would be used by the mmap
> > functions.
> 
> snd_pcm_write() and snd_pcm_read(), IIRC, allow reads&writes of chunks
> of data that are not period-sized.

Yes.  So does snd_pcm_mmap_commit().

> do you have an alternate explanation for louis' timing observations?

Apparently a different algorithm.
Louis, can we see your program?


Best regards,
Clemens