On Thu, 2005-03-03 at 17:05 +0000, Rui Nuno Capela wrote: > Spencer, > > > > Rui said a while ago that he was getting a similar message, until > > he tuned the IRQ priorities, but I've been googling around and I > > can't figure out how to do it. I tried > > chrt -f -p 90 'pidof "IRQ 0"' > > as directed on some website, but it just returns > > > > execvp: No such file or directory > > failed to execute pidof "IRQ 0" > > > > When I said that I was assuming that you have Ingo Molnar's > realtime-preempt patch, which applies to vanilla 2.6 kernels only (latest > is 2.6.11-rc4). The patch is here: > http://people.redhat.com/~mingo/reatime-preempt/ > You can only do that IRQ tunning if you have this kernel configured with > PREEMPT_RT=y (i.e. complete realtime-preemption enabled). > > Once you have this up and running, tune the IRQ threads (with chrt) like > this example: > > timer: chrt -f -p 90 `pidof "IRQ 0"` > rtc: chrt -f -p 80 `pidof "IRQ 8"` > snd: chrt -f -p 70 `pidof "IRQ 5"` > usb: chrt -f -p 60 `pidof "IRQ 10"` > > Please note you must check which IRQ numbers are the appropriate (cat > /proc/interrupts); the above is just an example taken from my laptop, > where the USB controller (ohci_hcd) is on IRQ 10 and the onboard sound is > on IRQ 5. YMMV. Also you can't change the priority of the timer IRQ thread (IRQ 0) anymore, because it does not run in a thread. This is not a problem. Lee
