Re: [proaudio] realtime problems (maybe pam)

["Kjetil S. Matheussen" <k.s.matheussen@xxxxxxxxxx>]

On Thu, 2 Oct 2008, Frieder Bürzele wrote:

> Kjetil S. Matheussen wrote:
> > On Wed, 1 Oct 2008, Frieder Bürzele wrote:
> >
> > > Kjetil S. Matheussen wrote:
> > > > On Wed, 1 Oct 2008, Frieder Bürzele wrote:
> > > >
> > > > > Mysth-R wrote:
> > > > > > are you in the audio group ?
> > > > > > Check on the /etc/group file.
> > > > > yes
> > > >
> > > > I have given up messing around with this pam/rt_limits/etc. thing, and
> > > > just manually forced the kernel to let me do what I want:
> > > >
> > > > http://archive.notam02.no/arkiv/src/realtime.diff
> > > >
> > > > Much easier.
> > > I've applied your patch, what else I've to do? disable pam?
> > > I still can't get realtime to work
> >
> > I don't know. That should be it. The patch just
> > shortcuts all other methods and just say yes
> > to everyone for all requests about scheduling property,
> > nice values and memory locking.
> >
> > It's definitely interesting that you still can't get
> > realtime to work, but I have no idea why. At least
> > you now know that there was probably nothing wrong
> > with pam before.
> >
> > But are you really sure realtime does not work?
> > How do you know?
> > (I seem to have deleted the mails in this thread)
>
> jack gives me that
>
> jackd -R -dalsa
>
> jackd 0.112.1
> 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.
> cannot use real-time scheduling (FIFO at priority 10) [for thread 1808877296, from thread 1808877296] (1: Operation not permitted)
> cannot create engine

Hmm, maybe I have misunderstood how pam works...

Can you try this program?


#include <sched.h>
#include <stdio.h>

int main(){
  struct sched_param par={0};
  par.sched_priority=99;
  if((sched_setscheduler(0,SCHED_FIFO,&par)!=0))
    printf("Not realtime\n");
  else
    printf("Realtime\n");
  return 0;
}