power saving

[Teresa e Junior]

Em 11/12/2017 21:59, Teresa e Junior escreveu:
> Em 11/12/2017 21:57, Teresa e Junior escreveu:
>> Em 11/12/2017 18:11, Xen escreveu:
>>> Teresa e Junior schreef op 11-12-2017 20:57:
>>>> Em 11/12/2017 15:31, Xen escreveu:
>>>>>
>>>>> The default profiler activated by the Linux kernel is apparently 
>>>>> "performance" which never lowers the frequency.
>>>>>
>>>>> The "cpufrequtils" package does nothing other than set the profiler 
>>>>> at boot and provide utils to set and read it.
>>>>
>>>> That's interesting. I'm on Xubuntu 17.10 with the default Ubuntu
>>>> kernel, and it is currently set to "powersave" without cpufrequtils
>>>> installed, although there is CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
>>>> on /boot/config-$(uname -r).
>>>>
>>>> So I don't really know what is controlling these settings on my laptop.
>>>
>>> Is there a power settings dialog screen in Xubuntu?
>>>
>>> KDE doesn't seem to have it.
>>>
>>> But "powersave" is not exactly ideal.
>>>
>>> I would say "conservative" is ideal if you want to save power,
>>>
>>> but powersave handicaps your CPU... :-/ ?.
>>>
>>
>> Yes, there is the xfce4-power-manager, but it has no options for 
>> dealing with the CPU, only things like screen brightness, actions on 
>> low battery, etc.
> 
> Actually, according to APT it does, but I see no such option in its 
> settings:
>     * battery monitoring
>     * cpu frequency settings
>     * monitor DPMS settings
>     * suspend/Hibernate
>     * LCD brightness control
>     * Lid, sleep and power switches control
>  > I'll have to investigate...

It doesn't handle CPU freq anymore: 
https://git.xfce.org/xfce/xfce4-power-manager/commit/?id=c76cf0295748a9d2260b3d3375e1633c6984b61c

But I have just noticed 
/sys/devices/system/cpu/cpufreq/policy*/scaling_available_governors have 
"performance powersave" only, but 
/sys/devices/system/cpu/intel_pstate/status returns "active" and 
/sys/devices/system/cpu/intel_pstate/turbo_pct "27", so I guess these 
are being handled by pstate and everything's alright :P

I had just forgotten that intel_pstate supersedes acpi_cpufreq.