freebsd stable - Nov 2018 - high cpu irq load and slow boot after update from 10.4 to 11.2

On Mon, 26 Nov 2018 19:34:43 +0700 Eugene Grosbein <eugen at grosbein.net>
wrote about Re: high cpu irq load and slow boot after update from 10.4 to
11.2:

> > Any ideas?
> Maybe this box has some clocking problems incompatible with tickless
> kernel. 
Is there anything I could look out for in dmesg or similar to spot the
root cause for this behaviour? The CPUs are Xeon E5606 on a Supermicro
X8DTU mainboard.
> Try get back to old periodic ticking with sysctl
> kern.eventtimer.periodic=1 instead of now default 0.
I'll try that as soon as I spot the issue again.
> Of, if you are curious, run ntpd if it is not already running, wait
> about an hour then look to its /var/db/ntpd.drift file to see if system
> clock is good or not.
ntpd is always running. Right now it looks ok to me (but the issue is not
there, either).

root at storage:~ # cat /var/db/ntpd.drift
-1.366
> Perhaps, you can get better behaviour changing default value
> of kern.timecounter.hardware to another one from kern.timecounter.choice;
> same with kern.eventtimer.timer and kern.eventtimer.choice
Would that work while I see the issue (i.e., should it make the issue go
away then), or should this be set on (re)boot?

Which settings would be recommended to try? This is what I have now:

---
root at storage:~ # sysctl kern.timecounter.hardware
kern.timecounter.hardware: TSC

root at storage:~ # sysctl kern.timecounter.choice
kern.timecounter.choice: ACPI-safe(850) HPET(950) i8254(0) TSC(1000)
dummy(-1000000)

root at storage:~ # sysctl kern.eventtimer.timer
kern.eventtimer.timer: LAPIC

root at storage:~ # sysctl kern.eventtimer.choice
kern.eventtimer.choice: LAPIC(600) HPET(350) HPET1(340) HPET2(340)
HPET3(340) i8254(100) RTC(0)
---


Thanks for your input.


cu
  Gerrit

26.11.2018 20:14, Gerrit K?hn wrote:
> Which settings would be recommended to try? This is what I have now:
> 
> ---
> root at storage:~ # sysctl kern.timecounter.hardware
> kern.timecounter.hardware: TSC
> 
> root at storage:~ # sysctl kern.timecounter.choice
> kern.timecounter.choice: ACPI-safe(850) HPET(950) i8254(0) TSC(1000)
> dummy(-1000000)
> 
> root at storage:~ # sysctl kern.eventtimer.timer
> kern.eventtimer.timer: LAPIC
> 
> root at storage:~ # sysctl kern.eventtimer.choice
> kern.eventtimer.choice: LAPIC(600) HPET(350) HPET1(340) HPET2(340)
> HPET3(340) i8254(100) RTC(0)
> ---
Try switching to "HPET" in both cases and do not wait for next
disaster
but do it right now with sysctl command, reboot is not needed.
You can restore default settings any moment same way.

And see if the problem goes away.