[PlanetCCRMA] Help with APIC/IRQ setup...

Fernando Lopez-Lezcano nando@ccrma.Stanford.EDU
Wed Jun 22 12:35:27 2005


On Wed, 2005-06-22 at 11:58, Brian Jarrett wrote:
> The only thing I've noticed is some pops when I was recording a single
> track in Ardour, but I've not really done anything to configure it and
> haven't done much else with my new system.
> 
> I was just following the instructions and attempting to tune the system.
> *grin*

If you are using the "rdt" edge kernels then the tuning is mostly done
automatically through the rtirq startup script (which sets the realtime
priorities of the lower half of the interrupts processes). I see that
the sound card appears to share an interrupt with the video card, you
may want to move the soundcard to a different slot to see which irq it
picks up. It is unlikely that the bios will let you assign interrupts to
individual pci slots (although it is possible). 

-- Fernando

> > -----Original Message-----
> > From: Mark Knecht [mailto:markknecht@gmail.com]
> > Sent: Wednesday, June 22, 2005 12:48 PM
> > To: Brian Jarrett
> > Cc: planetccrma@ccrma.stanford.edu
> > Subject: Re: [PlanetCCRMA] Help with APIC/IRQ setup...
> > 
> > Do you need to do anything? You don't speak of any xrun problems here.
> > Are you having any troubles with the default setup that would really
> > require a change?
> > 
> > - Mark
> > 
> > On 6/22/05, Brian Jarrett <bjarrett@garcoschools.org> wrote:
> > > Hello all,
> > >
> > > I've got a Gigabyte K8NS Ultra939 MB w/AMD64 CPU and 2 SATA HDD.
> > >
> > > I've installed 32bit FC3 and loaded "the Planet" audio apps.
> > >
> > > I haven't been able to "tune" the system by adjusting IRQs, or
> causing
> > > the system to do it, and I'm not even sure if I need to.  Here's my
> > > /proc/interrupts:
> > >
> > >            CPU0
> > >   0:     267756    IO-APIC-edge  timer
> > >   1:        268    IO-APIC-edge  i8042
> > >   8:          1    IO-APIC-edge  rtc
> > >   9:          0   IO-APIC-level  acpi
> > >  12:       1766    IO-APIC-edge  i8042
> > >  15:        864    IO-APIC-edge  ide1
> > >  16:      21284   IO-APIC-level  ICE1712, nvidia
> > >  17:      12942   IO-APIC-level  libata
> > >  18:          3   IO-APIC-level  ohci1394
> > >  20:          2   IO-APIC-level  ehci_hcd
> > >  21:          0   IO-APIC-level  NVidia CK8S, ohci_hcd
> > >  22:      23934   IO-APIC-level  ohci_hcd, eth0
> > > NMI:          0
> > > LOC:     267680
> > > ERR:          0
> > > MIS:          0
> > >
> > > I don't see any way to turn off APIC in the BIOS and I've tried
> > > kernel-level options "noapic" and "apic=off" but it seems to have no
> > > effect.
> > >
> > > Of course, I'd like my Delta66 (ICE1712) to have as high a priority
> as
> > > possible.  The things I have tried are a result of reading a lot of
> > > information that doesn't even really apply directly to dealing with
> > > APIC.
> > >
> > > Any suggestions?  I'm out of ideas, if there's anything I can even
> do
> > > about it.
> > >
> > > Brian
> > >
> > > _______________________________________________
> > > PlanetCCRMA mailing list
> > > PlanetCCRMA@ccrma.stanford.edu
> > > http://ccrma-mail.stanford.edu/mailman/listinfo/planetccrma
> > >
> 
> 
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