Increase laptop battery life: A Simple Bash Script

resource-limiter

#!/bin/bash

# Change Settings
cpu_threshold=30 # max percentage
memory_threshold=95 # max percentage
processes="chrome,code" # Processes to monitor and kill (comma-separated)

# Article to read more: https://dev.to/rahuldhole/managing-resource-deadlocks-a-simple-bash-script-for-linux-1n64

# Function to monitor CPU usage
monitor_cpu() {
    cpu_usage=$(top -bn2 | grep '%Cpu' | tail -1 | grep -P '(....|...) id,' | awk '{print 100-$8}')

    if awk -v cpu_usage="$cpu_usage" -v cpu_threshold="$cpu_threshold" 'BEGIN { exit !(cpu_usage >= cpu_threshold) }'; then
        logger -p user.warning "CPU usage is high ($cpu_usage%), killing selected processes."
        kill_processes
    fi
}

# Function to monitor memory usage
monitor_memory() {
    memory_usage=$(free -m | grep 'Mem:' | awk '{ print $3/$2*100 }')

    if awk -v memory_usage="$memory_usage" -v memory_threshold="$memory_threshold" 'BEGIN { exit !(memory_usage >= memory_threshold) }'; then
        logger -p user.warning  "Memory usage is high ($memory_usage%), killing selected processes."
        kill_processes
    fi
}

# Function to kill selected processes
kill_processes() {
    IFS=',' read -ra process_list <<< "$processes"

    for process in "${process_list[@]}"; do
        pkill -f "$process"
    done
}

# Main logic
monitor_cpu
monitor_memory