[PlanetCCRMA] issues starting jack as root

J. Scott Amort jsamort@shaw.ca
Sat Feb 7 12:29:00 2004

On Sat, 2004-02-07 at 10:47, Tim Currie wrote:
>    I have one small (I think) problem. I tinkered with jack and got it 
> running with both of my sound cards, but I had drop-outs and such, so I 
> decided to run it as root. The problem I have now is that only clients 
> (such as the incredible Ardour) started as root can connect to the jack 
> server.

If you are running from the PlanetCCRMA jack rpms, this is not
necessary.  jackstart is set to run with suid root (i.e. it gets root
privileges without actually being run as root).  Your drop-outs are
likely a symptom of improper jack settings.

>    So, my question is this: if I start jack as root, am I required to 
> run all my other stuff as root as well? Or, is there a way to get 
> non-root clients to connect to a root-owned jack server?

No, if you run jack as root, you have to run all the clients as root. 
But as I said above, this is not necessary, just use jackstart as a
regular user.

> [root@hamster root]# jackstart -R -d alsa -d hw:0 -p 512 -n 32 -r 44100

Your setting for 32 periods seems a bit strange, and that may be your
problem.  A -n of 2 is more common.  What soundcard is this?  You should
also give qjackctl a try.  It is included with the Planet, and gives a
nice GUI to try out different settings with jack without having to type
in a long command line each time.  Play with the frames per period and
number of periods (i.e. -p and -n settings) until you don't have any
dropouts, and then try some more aggressive settings until the xruns
come back.  Then you will know the limits of your soundcard/hardware.

Good luck!