[LAU] jackd thinks it's got realtime priority, but it doesn't

[Paul Coccoli]

I just noticed this on my Fedora 17 system.  I run jackd like this:

[paul at watt ~]$ /usr/bin/jackd --realtime -dalsa -dhw:0 -r48000 -p512 -n2
jackdmp 1.9.9.5
Copyright 2001-2005 Paul Davis and others.
Copyright 2004-2012 Grame.
jackdmp comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details
no message buffer overruns
no message buffer overruns
no message buffer overruns
JACK server starting in realtime mode with priority 20
audio_reservation_init
Acquire audio card Audio0
creating alsa driver ... hw:0|hw:0|512|2|48000|0|0|nomon|swmeter|-|32bit
configuring for 48000Hz, period = 512 frames (10.7 ms), buffer = 2 periods
ALSA: final selected sample format for capture: 32bit integer little-endian
ALSA: use 2 periods for capture
ALSA: final selected sample format for playback: 32bit integer little-endian
ALSA: use 2 periods for playback
Using port names patch v0.1 (07.04.2010)
Trying to load portnames from /home/paul/.config/jack/cards/M Audio
Delta 66.ss.ports.in
Trying to load portnames from /home/paul/.config/jack/cards/M Audio
Delta 66.ports.in
Trying to load portnames from /etc/jack/cards/M Audio Delta 66.ss.ports.in
Trying to load portnames from /etc/jack/cards/M Audio Delta 66.ports.in
Trying to load portnames from /home/paul/.config/jack/cards/M Audio
Delta 66.ss.ports.out
Trying to load portnames from /home/paul/.config/jack/cards/M Audio
Delta 66.ports.out
Trying to load portnames from /etc/jack/cards/M Audio Delta 66.ss.ports.out
Trying to load portnames from /etc/jack/cards/M Audio Delta 66.ports.out

Everything looks fine, and jackd claims it has realtime mode.  I've
been away from Linux audio for a while, but doesn't realtime mode mean
RT scheduling?  If I check the process's scheduler policy and
priority, it is NOT RT:

[paul at watt ~]$ ps -p 20370 -o cmd,class,pri,rtprio
CMD                         CLS PRI RTPRIO
/usr/bin/jackd --realtime - TS   19      -

I've added myself to the jackuser group:

[paul at watt ~]$ groups
paul wheel dialout wireshark jackuser

That group is already set up properly:

[paul at watt ~]$ cat /etc/security/limits.d/95-jack.conf
# Default limits for users of jack-audio-connection-kit

@jackuser - rtprio 70
@jackuser - memlock 4194304

@pulse-rt - rtprio 20
@pulse-rt - nice -20

Anyone have any idea what's going on here?