10 Jan
2018
10 Jan
'18
12:54 a.m.
On Tue, January 9, 2018 5:31 pm, Jonathan E. Brickman wrote:
JACK1 is single-core, JACK2 can spread itself out.
But on my big
production box, an 8-core 4GHz with 8G RAM, at last test, I was using
25% of CPU spread out evenly, but showing 75% of JACK DSP resources in
use. Therefore there's a lot left over that I can't get at, with just
one JACK2 process. :-)
Without knowing what the connection graph looks like it is difficult to
say whether there is opportunity to spread the load across multiple cores.
Having the DSP load so high compared to CPU load indicates that for the
period length you have chosen there is a lot of overhead. The most
reliable way to address that is to increase the period size.
If using jackd 1.9.x evaluate whether there is some connection between
ports that could be eliminated to make the connections available to be
split across processors. I think htop should show you how many jackd
threads are in use.
Last resort (as an end user) would be tuning the software so that it runs
more efficiently (e.g. making sure only true real time operations are done
in the RT thread, and moving everything else to a separate thread). As a
developer that should be first resort.
--
Chris Caudle