Re: PROBLEM: Cpufreq constantly keeps frequency at maximum on 4.5-rc4

[Rik van Riel <riel@redhat.com>]

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On Tue, 2016-03-01 at 09:06 +0200, Arto Jantunen wrote:
> Rik van Riel <riel@redhat.com> writes:
> 
> > What exactly is the problem you are seeing, and on what CPUs?
> 
> Quoting from the first mail in this thread:
> 
> When using kernel 4.5-rc4 my Skylake machine runs very warm since all
> cpu cores are always kept at 3.10Ghz (with maximum without turboboost
> being 2.6Ghz), completely regardless of load. Swapping between the
> governors (performance and powersave) doesn't change the result in
> any
> way, frequency remains at a constant 3.10Ghz.

> > What does the cpufreq table for that CPU look like?
> > 
> > Does HLT (or its equivalent) have a really, really high
> > exit or residency latency?
> 
> I don't know the answer to either of these questions. How do I find
> out?

Could you run this?

#!/bin/sh
for i in `seq 0 10`; do
	if [ -d /sys/devices/system/cpu/cpu0/cpuidle/state$i ]; then
		echo -n "state $i latency: "
		cat
/sys/devices/system/cpu/cpu0/cpuidle/state$i/latency
	fi
done

-- 
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