2009/2/14 Emanuel Rumpf :
Ah ... fine !
At LAU-ML, I found a message (02.02.2009) by Robin Gareus,
which solves the problem:
`echo -1 > /proc/sys/kernel/sched_rt_runtime_us`
or edit /etc/sysctl.conf and add:
kernel.sched_rt_runtime_us = -1
and his comment:
indeed, jackd did not start unless run as root or until I changed
It's the us (or .001% of CPU usage?!) above which FIFO and RR will be
throttled to recover from a run-away rt process. - I'm not exactly sure
why it affects jackd when run as "normal" user; maybe because with CPU
load above the default 95% rt can not be guaranteed.
There's a bit [off topic] but enlightening info at
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