CachyOS Power Management - ryzendew/Linux-Tips-and-Tricks GitHub Wiki

CachyOS Power Management Guide

Complete beginner-friendly guide to power management on CachyOS, including laptop battery optimization, CPU frequency scaling, and power saving features.

Table of Contents

  1. Understanding Power Management
  2. Laptop Battery Optimization
  3. CPU Frequency Scaling
  4. Power Profiles
  5. Advanced Power Settings
  6. Troubleshooting

Understanding Power Management

What is Power Management?

Power management controls how system uses power.

What it does:

  • Battery life: Extends laptop battery life
  • Performance: Balances performance and power
  • Heat management: Reduces heat generation
  • Efficiency: Improves power efficiency

Why it matters:

  • Laptops: Extends battery life
  • Desktops: Reduces power consumption
  • Heat: Reduces system heat
  • Cost: Saves electricity

Laptop Battery Optimization

Check Battery Status

Check battery:

upower -i /org/freedesktop/UPower/devices/battery_BAT0

What this does:

  • Shows battery information
  • Shows charge level
  • Shows battery health

Or use:

cat /sys/class/power_supply/BAT0/capacity

What this does:

  • Shows battery percentage
  • Simple battery level
  • Quick check

TLP Power Management

Install TLP:

sudo pacman -S tlp tlp-rdw

What this does:

  • Installs TLP power management
  • tlp-rdw: Radio device wizard
  • Automatic power optimization

Start TLP:

sudo systemctl enable --now tlp.service

What this does:

  • Enables TLP at boot
  • Starts TLP immediately
  • Applies power settings

TLP automatically optimizes:

  • CPU frequency scaling
  • GPU power management
  • Wi-Fi/Bluetooth power
  • USB autosuspend

TLP Configuration

Edit TLP config:

sudo nano /etc/tlp.conf

Common settings:

CPU_SCALING_GOVERNOR_ON_AC=performance
CPU_SCALING_GOVERNOR_ON_BAT=powersave

What this does:

  • performance: Full performance on AC
  • powersave: Power saving on battery
  • Balances performance and battery

Apply changes:

sudo tlp start

What this does:

  • Applies TLP settings
  • Updates power configuration
  • Takes effect immediately

CPU Frequency Scaling

CPU Governors

CPU governors control CPU frequency.

Available governors:

  • performance: Maximum frequency
  • powersave: Minimum frequency
  • ondemand: Scales based on load
  • conservative: Gradual scaling
  • schedutil: Modern scheduler-based

Check Current Governor

Check governor:

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

What this does:

  • Shows current governor
  • Verifies CPU scaling
  • Helps identify settings

List available governors:

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors

What this does:

  • Lists available governors
  • Shows options
  • Helps choose governor

Set CPU Governor

Set governor:

echo powersave | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

What this does:

  • Sets powersave governor
  • Applies to all CPUs
  • Saves power

Set performance:

echo performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

What this does:

  • Sets performance governor
  • Maximum CPU frequency
  • Better performance

Power Profiles

Using power-profiles-daemon

Install:

sudo pacman -S power-profiles-daemon

Start:

sudo systemctl enable --now power-profiles-daemon.service

What this does:

  • Provides power profiles
  • GUI integration
  • Easy power management

Power profiles:

  • Performance: Maximum performance
  • Balanced: Balanced performance/power
  • Power-saver: Maximum power saving

Switch profiles:

powerprofilesctl set performance
powerprofilesctl set balanced
powerprofilesctl set power-saver

What this does:

  • Switches power profile
  • Applies immediately
  • Changes system behavior

GUI Power Settings

GNOME:

  • Settings → Power
  • Select power profile
  • Adjust settings

KDE Plasma:

  • System Settings → Power Management
  • Configure power profiles
  • Set battery thresholds

Advanced Power Settings

CPU Frequency Limits

Set maximum frequency:

echo 2000000 | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq

What this does:

  • Limits CPU to 2GHz
  • Reduces power consumption
  • Lowers heat generation

Set minimum frequency:

echo 800000 | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq

What this does:

  • Sets minimum CPU frequency
  • Prevents too low frequency
  • Maintains responsiveness

Disable CPU Cores

Disable cores (advanced):

echo 0 | sudo tee /sys/devices/system/cpu/cpu3/online

What this does:

  • Disables CPU core
  • Reduces power consumption
  • ** May affect performance**

Re-enable:

echo 1 | sudo tee /sys/devices/system/cpu/cpu3/online

GPU Power Management

NVIDIA:

sudo nvidia-smi -pm 1
sudo nvidia-smi -pl 100

What this does:

  • Enables persistence mode
  • Sets power limit
  • Manages GPU power

AMD:

  • Usually automatic
  • Check with:
cat /sys/class/drm/card0/device/power_state

Troubleshooting

Battery Not Detected

Check battery:

ls /sys/class/power_supply/

What this does:

  • Lists power supplies
  • Shows if battery detected
  • Helps troubleshoot

Check kernel messages:

dmesg | grep -i battery

What this does:

  • Shows battery-related messages
  • Helps identify issues
  • Troubleshooting information

Power Settings Not Applying

Check TLP:

sudo systemctl status tlp

What this does:

  • Checks TLP status
  • Verifies it's running
  • Helps troubleshoot

Restart TLP:

sudo systemctl restart tlp

What this does:

  • Restarts TLP service
  • Applies settings
  • May fix issues

High Power Consumption

Check CPU usage:

top

What this does:

  • Shows CPU usage
  • Identifies power hogs
  • Helps optimize

Check processes:

ps aux --sort=-%cpu | head

What this does:

  • Shows top CPU processes
  • Identifies resource hogs
  • Helps optimize power

Additional Resources

Summary

This guide covered:

  1. Understanding power management - What it is and why it matters
  2. Laptop battery optimization - Extending battery life
  3. CPU frequency scaling - CPU governors and scaling
  4. Power profiles - Easy power management
  5. Advanced settings - CPU limits, GPU power
  6. Troubleshooting - Common power issues

Key Takeaways:

  • Use TLP for automatic power optimization
  • Set CPU governor based on needs
  • Use power profiles for easy management
  • Monitor battery and power consumption
  • Balance performance and power saving
  • Check processes for power hogs
  • Configure power settings for your use case

This guide is based on the CachyOS Wiki and Arch Linux Wiki and expanded with detailed explanations for beginners. For the most up-to-date power management information, always refer to the official documentation.