[LAU] Isolating/dedicating Interrupts

Ede Wolf listac at nebelschwaden.de
Mon Nov 23 17:38:39 UTC 2015

Thanks for all your help and input, part of it improved the situation. 
Now, before further praise, just one more realted topic I haven't found 
any information of.
Since I was on a budget and to avoid HT and onboard video I went AMD and 
now, having 8 cores (albeit only 4 FPUs, which, as I've learned here, 
are not so relevant for FX unless using convolution reverbs), I wonder 
wether it makes any sense to dedicate one core to jack?

So adding isolcpus=7 to your kernel parameters and running jack (and 
maybe zita bridge) with tasksel -c 7? And maybe even bind that soundcard 
IRQ to that CPU as well?
Since jack does not support smp anyway, there is nothing to lose, but 
some given away CPU cycles, as that CPU will be bored and not be 
available for other tasks.

Complete nonsense? Since my setup is not really finished due to some KVM 
Problems, which most likely will require adding another PCIe card, I 
currently cannot test thoroughly.

Back to praise, as I've been able to get that USB9 from named interrupt 
by unbinding it, killing my mouse instantly, but I found another port, 
and by disabling USB3 alltogether using the same method. Don't see me 
using that for the forseeable future. However, it seems I will have to 
add a serial port card, which then will request another IRQ again. So my 
mainboard is pretty packed, and instead of moving cards I can only swap 
them. Nothing to gain here IRQ wise.

I do remember when one could assign IRQs to specific slots, but that was 
pre PCIe era. Indeed a shame, especially since we now have 50+ instead 
of the former only 15 or 16 IRQs. But steadily losing control is simply 
the future of anything technology related.

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