CPU - Synced VS Independent Core OC/UC

LocoMoto

DEVOURER OF BAKED POTATOES
Original poster
Jul 19, 2015
287
335
Hey y'all!

Have thought a lot about the best way to clock your CPU and have for some time been thinking about independently clocking your CPU cores and doing so to get the best performance you can for a given power target.
Coming from a thought that perhaps some cores are utilized more than others, that power should be set aside for those cores in order to get them towards a higher frequency and save power on the less utilized ones.

Is there anyone here that have tried it out and recorded their results, anyone who has knowledge from the software side of this or anyone with their thesis on the matter?
Please share, I'm myself planning to set aside some time to test this out soon enough and will record the results I get.

Thanks for the time everyone! :)
 

Soul_Est

SFF Guru
SFFn Staff
Feb 12, 2016
1,536
1,928
I have worked on this under Linux and it does happen already. Intel's Enhanced SpeedStep and AMD's Turbo Core technologies handle this on the hardware side while CPU frequency governors handle this on the software side (and only if you enable them. First thing I did after getting a ThinkPad X200s in 2012 was to figure out how to lower the power consumption. CPU performance played a large role in that.

Here's the output from cpupower on my ThinkPad X201:

Code:
sudo cpupower frequency-info w
analyzing CPU 0:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 10.0 us
  hardware limits: 1.20 GHz - 2.53 GHz
  available frequency steps:  2.53 GHz, 2.53 GHz, 2.40 GHz, 2.27 GHz, 2.13 GHz, 2.00 GHz, 1.87 GHz, 1.73 GHz, 1.60 GHz, 1.47 GHz, 1.33 GHz, 1.20 GHz
  available cpufreq governors: performance schedutil
  current policy: frequency should be within 1.20 GHz and 2.53 GHz.
                  The governor "schedutil" may decide which speed to use
                  within this range.
  current CPU frequency: 2.53 GHz (asserted by call to hardware)
  boost state support:
    Supported: yes
    Active: yes
    2100 MHz max turbo 2 active cores
    2300 MHz max turbo 1 active cores

This is without having any CPU frequency governors on since I usually use the system docked.
 

EdZ

Virtual Realist
May 11, 2015
1,578
2,107
Hey, can you play with this stuff on a non-K chip? I'd love to play with my work laptop's settings some time if it meant better battery life.
If you just want to drop power consumption by lowering the max power target, this is really easy to do from the Advanced Power Options if you are using Windows:

The CPU will manage its own frequency and voltage in order to stay within this power budget.