[ANNOUNCE] New Mixer Handling in PA 0.9.16/F12

[Adam Williamson]

On Wed, 2009-07-29 at 15:26 +0200, Michal Hlavinka wrote:

> > If PA eats a lot of CPU this can have many reasons, most of them have
> > to do with the latency settings requested by the applications  or that
> > have been configured due to frequent underruns. However the actual
> > mixing is certainly the smallest part of it. Plese don't forget that
> > mixing is not exactly the most complex operation on earth.
> 
> Well... I'm pretty sure I have no idea how it works :D I've just noticed that 
> when playing stereo and sound card (Aureon MK II) is configured for stereo, it 
> eats about 4 % and (when speakers are set as 5.1) only front speakers work (as 
> expected), when I configure that card for 5.1 output and play stereo stream it 
> goes to all 5.1 speakers and eats about 24 % of cpu

That's not mixing, it's multiplexing. I don't think any card has ever
had hardware acceleration for that operation (though hey, I'm probably
wrong ;>).

Mixing is what happens when you play sound from two or more applications
at once.

-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Fedora Talk: adamwill AT fedoraproject DOT org
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