[pulseaudio-discuss] Using PA with multiple sound cards

[Colin Guthrie]

'Twas brillig, and Mark Greenwood at 21/03/09 23:45 did gyre and gimble:
> High CPU usage problem:
> 
> Machine one: Use paprefs to enable 'Enable network access to local
> sound devices' 'Allow other machines on the LAN to discover local
> sound devices' 'Don't require authentication'
> 
> Machine two: Use paprefs to enable 'Make discoverable network sound
> devices available locally'
> 
> As before, start Amarok playing some music. Use pavucontrol to Move
> Stream to the USB sound device on machine one (actually it doesn't
> matter, any device on machine one will do. I don't even need the USB
> device plugged in).
> 
> Audio starts playing out of machine one. CPU usage (run 'top') on
> both machines rises and rises. Machine one is very low-powered and on
> there the CPU usage reaches 99% and pulseaudio quits.

I thought I could replicate this earlier today, as pulse CPU did go very 
high for a while with network sinks, and it fell away when I unticked 
the boxes in paprefs. But I can't replicate now I try to sit down and 
look at it :s

That said, one end of my loop is 0.9.10 so not sure how valid a test 
this is. I'll try and upgrade the other side shortly.

> This is the best thing about Linux when it works. I'm starting to
> think I'm going mad; (I can't be the only one using the network
> stuff, surely? Why has nobody else reported this?)

To be fair there are probably not a huge number of people using 0.9.14. 
Quite a lot of distros stuck with 0.9.10 and are only shipping 0.9.14/15 
in the next round of releases which are coming up now.

And of those using the newer versions, only a small subset will use 
networking. So it's not surprising that you're the only one reporting 
this... you're a pioneer! Be proud! :p



To debug further, it would be good to run pulseaudio manually on each 
machine via -vvv args and see if anything is printed when the CPU goes 
skyward.

Col

-- 

Colin Guthrie
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http://colin.guthr.ie/

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