tesla-dev-bounces at opensolaris.org wrote:

> Liu, Jiang wrote:
>> Hi Aubrey,
>>      Thanks for your reminder.
>>      After reading relative code, I have some questions about DTrace
>> prober trigger point in deep C path. On SPARC and non-deep-C idle
>> path, DTrace probers have been placed as closer as possible to the
>> point that CPU enters into/exits from hardware idle state. On deep C
>> state path, the prober trigger points have been pulled out a little.
>> I heard there were some discussions about prober trigger points but
>> I missed those discussions. Could anybody give some hints about
>> those discussions? 
>> 
> 
> What does PowerTop measure and report on other operating systems?
> Does PowerTop's C-state data include the software latenct to
> enter/exit C-state(s)
> on other Operating Systems?  My current thought is Solaris
> should report
> the same
> measurement as other OSs.  :-)

Different OS is using different time resource.
My concern is, idle exiting dtrace probe was added into do_interrupt, which
will add too much latency when enabled. That might affect the current report.

We'd better to force idle exiting dtrace probe back to the idle thread.

> 
> Does LatencyTop show C-state entry/exit software-latency?

No, I don't think so.

Thanks,
-Aubrey

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