[linux-audio-user] pam modules / non root users can't get realtime privileges.

[Fernando Lopez-Lezcano]

On Sat, 2007-02-03 at 17:24 +0100, Marcos Guglielmetti wrote: 

Hola Marcos...

> El Sáb 03 Feb 2007 21:13, Ken Restivo escribió:
> > On Sat, Feb 03, 2007 at 04:48:31PM +0100, Marcos Guglielmetti wrote:
> > > What is happening? see:
> > >
> > > jackd -v -p128 -t2000 -m -dalsa -dhw:0 -r48000 -p512 -n2 -s -S -H
> >
> > Did you forget the "-R" flag to make jackd run in realtime?
> 
> Ouch, yes sorry, I was testing how does it goes without realtime, but.
> 
> Now, I did it Ok, and the problems are still here: no realtime, too much 
> xruns:
> 
> jackd -R -v -p128 -t2000 -m -dalsa -dhw:0 -r48000 -p512 -n2 -s -S -H
> 
> getting driver descriptor from /usr/lib/libjack0.100.0-0/jack_dummy.so
> getting driver descriptor from /usr/lib/libjack0.100.0-0/jack_oss.so
> getting driver descriptor from /usr/lib/libjack0.100.0-0/jack_alsa.so
> jackd 0.101.1
> Copyright 2001-2005 Paul Davis and others.
> jackd 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
> 
> JACK compiled with System V SHM support.
> server `default' registered
> loading driver ..
> registered builtin port type 32 bit float mono audio
> required capabilities not available
> capabilities: =

Hmmm, this does not sound right. 

Capabilities was an old hack to get things running as non-root with
2.4.x kernels (and the jackstart suid program). What options are you
building jack with? You don't need to / should not enable capabilities. 

This is what the startup looks like here:

----
$ jackd -v -R -d alsa -d hw
getting driver descriptor from /usr/lib/jack/jack_alsa.so
getting driver descriptor from /usr/lib/jack/jack_freebob.so
getting driver descriptor from /usr/lib/jack/jack_dummy.so
jackd 0.102.20
Copyright 2001-2005 Paul Davis and others.
jackd 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

JACK compiled with System V SHM support.
server `default' registered
loading driver ..
creating alsa driver ... hw|hw|1024|2|48000|0|0|nomon|swmeter|-|32bit
configuring for 48000Hz, period = 1024 frames, buffer = 2 periods
ALSA: final selected sample format for capture: 32bit little-endian
ALSA: use 2 periods for capture
ALSA: final selected sample format for playback: 32bit little-endian
ALSA: use 2 periods for playback
registered builtin port type 32 bit float mono audio
registered builtin port type 8 bit raw midi
clock source = system clock via gettimeofday
new client: alsa_pcm, id = 1 type 1 @ 0x9a997f8 fd = -1
new buffer size 1024
registered port alsa_pcm:capture_1, offset = 4096
registered port alsa_pcm:capture_2, offset = 8192
registered port alsa_pcm:playback_1, offset = 0
registered port alsa_pcm:playback_2, offset = 0
registered port alsa_pcm:playback_3, offset = 0
registered port alsa_pcm:playback_4, offset = 0
registered port alsa_pcm:playback_5, offset = 0
registered port alsa_pcm:playback_6, offset = 0
registered port alsa_pcm:playback_7, offset = 0
registered port alsa_pcm:playback_8, offset = 0
++ jack_rechain_graph():
client alsa_pcm: internal client, execution_order=0.
-- jack_rechain_graph()
22568 waiting for signals
load = 0.0281 max usecs: 12.000, spare = 21321.000
load = 0.0586 max usecs: 19.000, spare = 21314.000
jack main caught signal 2
starting server engine shutdown
stopping driver
unloading driver
freeing shared port segments
stopping server thread
stopping watchdog thread
last xrun delay: 0.000 usecs
max delay reported by backend: 0.000 usecs
freeing engine shared memory
max usecs: 19.000, engine deleted
no message buffer overruns
cleaning up shared memory
cleaning up files
unregistering server `default'
----

-- Fernando