Re: [patch] Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.32-6

[Ingo Molnar]

* Mark_H_Johnson@xxxxxxxxxxxx <Mark_H_Johnson@xxxxxxxxxxxx> wrote:

> >also, i'd like to take a look at latency traces, if you have them for
> >this run.
> 
> I could if I had any. The _RT run had NO latency traces > 250 usec
> (the limit I had set for the test). The equivalent _PK run had 37 of
> those traces. I can rerun the test with a smaller limit to get some if
> it is really important. My build of -12 is almost done and we can see
> what kind of repeatability / results from the all_cpus trace shows.

/me is puzzled.

so all the CPU-loop delays within the -RT kernel are below 250 usecs? I
guess i dont understand what this means then:

| The max CPU latencies in RT are worse than PK as well. The values for
| RT range from 3.00 msec to 5.43 msec and on PK range from 1.45 msec to
| 2.24 msec.

these come from userspace timestamping? So where userspace detects a
delay the kernel tracer doesnt measure any?

	Ingo
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