I've noticed since the very 1'st day I installed ubuntu 18.04 my battery life surprisingly reduced.so I checked system monitor. I noticed that only one of my CPU core is always run on high usage while other cores are in an idle stage. so I installed laptop model tools utility. then under the plugged stage, all the CPU cores work simultaneously with the same usage.i`ve attached two screenshots showing that 1st one is while on battery power 2nd one is just after plugged into power code.anyone can help me to optimize my CPU under the battery power?

CPU usage under battery power

CPU usage under battery power

CPU usage just after plugged into power

CPU usage just after plugged into power code

1 Answer 1


Since I did full research on this, I think I can answer my question by my self. I was able to fix this issue, The problem was Ubuntu does not support Intel new power management options. This was a kernel bug which was fixed by ubnutu little days ago.


so try these steps,

  1. sudo nano /etc/default/grub
  2. replace the line GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" with GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_idle.max_cstate=0"
  3. save it (CTRL+O)
  4. sudo update-grub
  5. sudo reboot

*(it is important to use intel_idle.max_cstate=0)

I will reference a similar kind of question to read and understand the situation a little more, but it`s the answer is different from this,

Clevo N850EL crashes/freezes Ubuntu 18.04.1 frequently

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