Re: [Jack-Devel] ALSA PCM multi plugin and xruns

On Mon, Dec 10, 2012 at 06:41:04PM +0000, John Rigg wrote:
> I've tried smp_affinity here and it hasn't fixed the problem. It just
> took longer for the xrun messages to show up.
> 
> I set the smp_affinity for the two ice1712 cards (which are on IRQ20
> and 21) to CPU1 in my test system with the following:
> echo "2" > /proc/irq/20/smp_affinity
> echo "2" > /proc/irq/21/smp_affinity
> 
> Then I started jackd with my pcm_multi device at 96kHz and started
> jamin to generate some load. At first it looked like this had worked,
> but after about 5 minutes the xrun indications in jamin started piling
> up. Both IRQs are definitely handled by CPU1 according to frequent
> checks using cat /proc/interrupts.
> 
> My test system uses an AMD 4850e Athlon64x2 2.5GHz CPU. Running jamin at
> 96kHz uses 11% CPU according to jamin's load indicator.

Another observation: the xruns seem to go in batches. There weren't any
for about 5 minutes, then over the next few minutes there were thousands.
A few minutes later they stopped again for a while, then started again
after another few minutes.

John

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