On Thu, 06 Sep 2012 10:02:11 -0700 Kevin Cosgrove <kevinc@xxxxxxxxxxxx> wrote: > > On 6 September 2012 at 8:43, Kevin Cosgrove <kevinc@xxxxxxxxxxxx> > wrote: > > > > >> cat /proc/interrupts > > > > > > > > Xrunning system says: > > > > > > > > CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7 > > > > 16: 56322 0 0 0 0 0 0 0 > > > > IO-APIC-fasteoi ahci, ehci_hcd:usb1, firewire_ohci, > > > > snd_ice1712, nvidia > > > > > > That would give me xruns too. > > > > OK. I see it now. I've never had to fight the interrupt problem > > before. > > > > > (if you can) See if you can set IRQ in the bios for that slot > > > to something else if there is only one. > > > > I'll look at the manual for my MB and see what I can do. > > I did a search for "irq" on this website > > http://www.manualowl.com/m/Asus/P8Z68-DELUXE%2FGEN3/Manual/263040?page=91 > > and found a page (2-14) that lists the (non-alterable???) IRQ > assignments for my motherboard. The good news is that one of > the legacy PCI slots has less stuff on the IRQ. The bad news > is that one of the PCI slots has lots of stuff on that IRQ. > > Looking at IRQ 16 above, my nVidia shows up. It's PCiE x16, > and my motherboard seems to have 3 of those slots, with one slot > being on a different IRQ. I suspect moving the video card might > help, right? > > Basically, my strategy would be to disable drivers I don't use. > For instance, I don't have any firewire gear. Next, I'd move > anything I could to a slot using a different IRQ than the one > I want to reserve for the Delta 1010. Seem like a good plan? FWIW, I have a similar system with an Asus P8Z68-V PRO GEN3 + Intel i7-2600k CPU, I have an rme multiface PCI card in a slot that gives it IRQ 18 all to itself. The only irq priority manipulation I do is to run chrt -f -p 98 `pgrep irq/18-snd_hdsp` from /etc/rc.local. I also have the system running with the default ondemand governor. I don't use an external NVIDIA card as the built in HD3000 GPU works a treat for low latency audio even with a full KDE install with compositing kwin. If I did use a NVIDIA card I would most likely use the nouveau driver that lately has become very good for low latency audio. Kernel is 3.4.9-rt17. Running cyclictest -m -Sp99 -i100 -d0 shows me kernel scheduling latencies of well under 0.1ms no matter how hard i push the system, and that is with the ondemand governor... All in all very pleased with this system, and I think you will be too if you move the soundcard to another slot, having less stuff on it. Another tip, if you have to use a slot that shares IRQs, then you have to raise the priority of all the soft interrupt threads that share the IRQ with the soundcard, otherwise you will get a lot of xruns. --- Joakim _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
