Re: [proaudio] rtlimits pam gentoo-sources

[Harald Gutmann <harald.gutmann@xxxxxxx>]

Harald Gutmann wrote:
>
>
> hmm ... intersting, when i start jackd with -P80 it works without the
> error, but starting it with -P81 and above the error alway's occours.
> could it be, that the memory buffer is too small for priority 81 and above?
>
>   
problem solved!
the reason was not the size of the memlock, but the rtprio value.
setting the rtprio value to 99, allows to start jackd with any priority
you want.

before it was set to 90, and that was to low for the realtime value of >80.
why?

let's see what "ps -C jackd -cmL" says:
  PID   LWP CLS PRI TTY          TIME CMD
15050     - -     - ?        00:00:04 jackd
    - 15050 TS   21 -        00:00:00 -
    - 15051 TS   21 -        00:00:00 -
    - 15052 TS   23 -        00:00:00 -
    - 15053 FF  139 -        00:00:00 -
    - 15054 FF  129 -        00:00:04 -

(that's with jackd running at realtime priority 89 (maximal value in
qjackctl))

and then look what chrt -p tells us about the subprocesses of jackd:
z421@winnie ~ $ chrt -p 15050
pid 15050's current scheduling policy: SCHED_OTHER
pid 15050's current scheduling priority: 0
z421@winnie ~ $ chrt -p 15051
pid 15051's current scheduling policy: SCHED_OTHER
pid 15051's current scheduling priority: 0
z421@winnie ~ $ chrt -p 15052
pid 15052's current scheduling policy: SCHED_OTHER
pid 15052's current scheduling priority: 0
z421@winnie ~ $ chrt -p 15053
pid 15053's current scheduling policy: SCHED_FIFO
pid 15053's current scheduling priority: 99
z421@winnie ~ $ chrt -p 15054
pid 15054's current scheduling policy: SCHED_FIFO
pid 15054's current scheduling priority: 89
z421@winnie ~ $
                                                                               

the highest schedule priority is in that case 99, also when the jackd
starting parameter -P has only value of 89.
with rtprio set to 90, and jackd started with realtime priority of 80,
the highest scheduling priority is on 90.
that was the problem, why i got an error with values over 80, when the
rtprio was set to 90.

best regards,
harald gutmann