[PlanetCCRMA] FC5 xruns

[Fernando Lopez-Lezcano]

On Mon, 2006-05-29 at 19:07 -0500, Link Swanson wrote:
> On Mon, May 29, 2006 3:27 pm, Fernando Lopez-Lezcano wrote:
> > On Mon, 2006-05-29 at 15:08 -0500, Link Swanson wrote:
> >> On Mon, May 29, 2006 1:37 pm, Fernando Lopez-Lezcano wrote:
> >> > On Mon, 2006-05-29 at 13:20 -0500, Link Swanson wrote:
> >> >> I recently upgraded a my FC4 CCRMA system, which ran free of xruns,
> >> to
> >> >> FC5, and now I get loads of xruns when running jack.
> >> >>
> >> >> I am running an HDSP Multiface and my motherboard sound is disabled.
> >> >>
> >> >> I'm a big noob so all help is welcome. Thanks
> >> >>
> >> >> Here is some JACK output:
> >> > How did you install the core Planet CCRMA components in fc5? (kernel,
> >> > etc). If you installed the meta package ("yum install
> >> > planetccrma-core-*") you should have a custom version of pam with
> >> > realtime scheduling and memory locking enabled for non-root users -
> >> and
> >> > the rtirq irq priority reordering startup script. See which version
> >> you
> >> > have ("rpm -q pam"), if it does not have a "rhfc5" in the release
> >> field
> >> > then you need to upgrade it to the Planet CCRMA version.
> >>
> >> Thanks Nando! yum install pam did the trick.
> >
> > Do you have rtirq? ("rpm -q rtirq").
> >
> >> One more question: I'm using onboard nVidia 6100 graphics and I get a
> >> "bleedthrough" effect: my sound crackles when I open windows, menus,
> >> move
> >> things accross the screen, etc. This occurs whether I'm using the "nv"
> >> drivers or the commercial drivers from nVidia. Is there any way I can
> >> relieve this? I do have another matrox PCI card I can use, but I'd
> >> rather
> >> use the onboard.
> >
> > Hard to know if it is the video card hogging the bus or is just analog
> > noise from a bad mobo design. Do you get xruns when that happens? Or is
> > it just noise?
> >
> > You may want to take a look at this:
> >   http://www-128.ibm.com/developerworks/library/l-hw2.html
> >
> > You could check the pci latency timers and see if changing the one for
> > the video card makes any difference.
> >
> > Also make sure you have rtirq installed and active, it will reorder the
> > interrupt priorities so that your soundcard has the best chance of
> > servicing interrupts first.
> >
> > -- Fernando
> 
> Installed rtirq but how do I make sure that rtirq is active?
> 
> Here's my IRQ settings. "nvidia" is on 18 and my hdsp is on 19. Any
> suggestions?
> 
> 
>   0:     443827  IO-APIC-edge   [........N/  0]  pit
>   1:         39  IO-APIC-edge   [........./  0]  i8042
>   7:          1  IO-APIC-edge   [..P....../  0]  parport0
>   8:          1  IO-APIC-edge   [........./  0]  rtc
>   9:          0  IO-APIC-level  [........./  0]  acpi
>  12:      26615  IO-APIC-edge   [........./  2]  i8042
>  14:      12620  IO-APIC-edge   [........./  0]  ide0
>  15:       1285  IO-APIC-edge   [........./  0]  ide1
>  16:          0  IO-APIC-level  [........./  0]  libata
>  17:      42000  IO-APIC-level  [........./  0]  eth0
>  18:      33816  IO-APIC-level  [........./  7]  nvidia
>  19:      31050  IO-APIC-level  [........./  0]  hdsp
>  20:          0  IO-APIC-level  [........./  0]  ohci_hcd:usb1
>  21:          0  IO-APIC-level  [........./  0]  ehci_hcd:usb2
> NMI:          0
> LOC:      33867
> ERR:          0
> MIS:          0

That only tells you which interrupts go where. What is important for
audio purposes (only when running kernels patched with Ingo's realtime
preemption patches) is the relative priority of the software processes
that actually service the interrupts. 

rtirq runs at boot time and reorders the priority of the interrupt
processes (that is independent of the hardware routing of the
interrupts). If you have not rebooted since you installed it you need
to:
  /etc/rc.d/init.d/rtirq start

You can see what the current status of interrupts is with:
  /etc/rc.d/init.d/rtirq status

-- Fernando