Power Management

The Problem

Éowyn’s performance when running Ubuntu was, at best, less than optimal, and at worst, abysmal.

From what the ArchWiki recommended, I’m testing out powertop, a “tool provided by Intel to enable various powersaving modes in userspace, kernel and hardware. It is possible to monitor processes and show which of them are utilizing the CPU and wake it from its Idle-States, allowing to identify applications with particular high power demands.”

I’m also testing out TLP for better power management.

Stuff to watch out for

  1. You’re going to want to keep powertop running for a bit only connected to battery power. If you don’t, powertop won’t have enough measurement data.

  2. Some folks have reported issues with powertop and USB. The fix is going to the Tunables selection, and changing the settings at the appropriate line from “Good” to “Bad.”

  3. You can calibrate using

     sudo powertop --calibrate
    

Setting up Powertop

  1. Install using

     sudo apt-get install powertop
    
  2. Type

     sudo powertop
    

    or sudo powertop –auto-tune Using the auto-tune flag changes all of the Tunables to “Good.”

  3. However, these changes aren’t permanent. If you want to make these changes permanent, install powertop as a service by typing the following:

     cat << EOF | sudo tee /etc/systemd/system/powertop.service
    
     [Unit]
     Description=PowerTOP auto tune
    
     [Service]
     Type=idle
     Environment="TERM=dumb"
     ExecStart=/usr/sbin/powertop --auto-tune
    
     [Install]
     WantedBy=multi-user.target
     EOF
    
     systemctl daemon-reload
     systemctl enable powertop.service
    
  4. You should be good to go! Check out this link for more info.

Installing TLP

  1. I installed TLP using

     sudo apt install tlp
    
  2. There’s an optional graphical UI for TLP called TLPUI. First, add the PPA repository using

     sudo add-apt-repository ppa:linuxuprising/apps
    
  3. Then, type

     sudo apt install tlpui
    
  4. If you don’t like TLP, uninstall using

     sudo apt remove --autoremove tlpui
    

    and go to Software & Updates -> Other Software to remove the PPA.

Undervolting CPU

At this point, I’m really, really, hating Éowyn; my honest recommendation to anyone is to just get something other than a Dell XPS 9570. My laptop heats up when I’m running something like Vim for about 5 minutes, and this is right after a fresh reboot/shut down. I’m at a loss. I tried using TLPUI to help me out on undervolting, and it’s kinda working, but not as effectively as I would have liked.

The power performance on Éowyn is now fine, but that may be some combination of moving from Ubuntu to Debian, and from GNOME to Cinnamon/i3. GNOME was probably a bit too bloated, as may have been other apps I tended to use. I really like my computer now!