3 Mar
2005
3 Mar
'05
1:17 p.m.
On Thu, 2005-03-03 at 17:05 +0000, Rui Nuno Capela wrote:
Spencer,
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
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.