[LAU] Too many xruns

[Kevin Cosgrove]

On 12 October 2012 at 14:33, Brendan Jones <brendan.jones.it at gmail.com> wrote:

> On 10/11/2012 06:17 PM, Kevin Cosgrove wrote:
> >
> > On 11 October 2012 at 6:55, Paul Davis <paul at linuxaudiosystems.com> wrote:
> >
> > > http://jackaudio.org/realtime_vs_realtime_kernel
> >
> > OK.  That's a pleasant answer.  :-)
> >
> > I added this:
> >
> > ::::::::::::::
> > /etc/security/limits.d/93-audio_limits.conf
> > ::::::::::::::
> > # Increase priority of audio applications
> > # maximum realtime priority
> > @audio - rtprio 90
> > # maximum locked-in-memory address space (KB)
> > @audio - memlock 2000000
> >
> >
> > Fedora's jack-audio-connection-kit-1.9.8-9.fc17.x86_64 package added this:
> >
> > ::::::::::::::
> > /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
> >
> >> you *must* get these permissions correct ...
> >
> > By permissions, are you meaning
> >
> >    crw-rw---- 1 root audio  10, 228 Oct 10 22:47 /dev/hpet
> >    crw-rw---- 1 root audio 254,   0 Oct 10 22:47 /dev/rtc0
> >
> >    [kevinc #28] groups
> >    kevinc root adm disk wheel cdrom man floppy games audio users jackuser
> >
> >>> 3.  Kernel with Real-Time Preemption... not found - not good
> >>
> >> not necessarily relevant. required in cases where the kernel and h/w are
> >> cooperating (badly) to prevent low latency operation, but many people have
> >> systems where this is not required.
> >
> > I'm having IRQ crowding issues, and I was headed at trying to
> > get rtirq going in order to help this.  I believe rtirq *does*
> > require an RT kernel.
> > http://wiki.linuxmusicians.com/doku.php?id=system_configuration#rtirq
> 
> the default values provided by jack in limits.d have been chosen to work 
> with the defaults in Fedora's rtirq package. You should only need to add 
> threadirqs to the kernel command line

I think it's working, because 'rtirq status' produces results, and 
those results show my audio stuff as the highest priority.  Earlier I 
was confused about threadirqs, thinking that it didn't work because
the RT kernel test reported that no RT kernel was found.

As for "Fedora's rtirq package", I had to get mine from CCRMA, not 
Fedora 17 repositories.  Were you implying that rtirq would be 
available from something other than CCRMA?  If so, what's the right 
F17 repository for this?

Thanks...

--
Kevin