First, hello! An audio newbie, and linux oldie here :o) When I used set_rlimits jackd ... there were less xruns then running jackdbus, but gladish is so comfortable, I don't want to switch back. I have set ulimits:
# ulimit -r -l
-l: locked-in-memory size (kb) unlimited
-r: max rt priority 85
But then ...
# ps ax -o user,rtprio,command | grep jack
meka - /usr/bin/jackdbus auto