[alsa-devel] [RFC] disabling ALSA period interrupts

Raymond Yau superquad.vortex2 at gmail.com
Fri May 14 05:09:55 CEST 2010

2010/5/14 pl bossart <bossart.nospam at gmail.com>

> > Refer to your patch "add rewind-safeguard parameter"
> >
> >
> http://git.0pointer.de/?p=pulseaudio.git;a=commit;h=4df443bbe682055a41e7c2248877dcc7682a69b8
> >
> > you mention glitch occur because application cannot rewind appl pointer
> to
> > hardware ptr.
> >
> > In another word, app ptr must be 128/256 bytes ahead of hardware ptr at
> any
> > time to prevent glitch occur. this mean that the glitch was due to DMA
> brust
> > size since "PulseAudio modilfies its watermark when underflows occur".
> Man, you are seriously confused. You ought to do some reading, look at
> the code, use your brain and figure things out instead of spamming
> this thread.

underrun is application pointer behind hardware pointer

"Rewinding the ring buffer completely causes audible issues with DMAs."

rewinding ring buffer compleletly mean hardware pointer = application

"Glitch free" can only be achieved when PA adjust the watermark before any
unnder run occur not "until underrrun occur" since it is too late

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