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

[Raymond Yau]

2010/4/30 pl bossart <bossart.nospam at gmail.com>

> Howdy,
> When PulseAudio is used and all PCM is routed through PulseAudio
> (Fedora, Meego, etc), the notion of ALSA periods isn't very useful.
> PulseAudio uses a timer to refill buffers and the period interrupts
> are not used at all.
>
> So why not disable them entirely to reduce the number of wakeups? This
> is possible with a number of existing DMA controllers. The simple
> patch attached shows a proof-of-concept on HDAudio, it's been working
> for 5 hours on my Fedora12 laptop without any glitches and powertop
> does show _zero_ wakeups from the HDAudio controller (except on
> startup). I am told by my colleagues working in Windows environments
> that this is what's done on Vista/Windows7 btw. This isn't to say
> Windows is great but that artificial generation of not-needed
> interrupts is avoidable.
>

Do your test need the patch which you have posted to pulseaudio developer
mailing list

http://thread.gmane.org/gmane.comp.audio.pulseaudio.general/6671

it seem that fix should be in driver side if it is hardware specific