check memory and restart service when less than X gb.

bash #!/bin/bash 
 # Get the available memory in KB free_mem_kb=$(free -k | grep Mem | awk '{print $4}') 
 # Convert to GB (divide by 1024^2) # without bc free_mem_gb=$((free_mem_kb / 1024 / 1024)) # with bc # free_mem_gb=$(echo "scale=2; $free_mem_kb / (1024 * 1024)" | bc) 
 # Threshold for memory in GB threshold=2 
 # Check if free memory is less than the threshold # without bc if [ "$free_mem_gb" -lt "$threshold" ]; then # with bc # if (( $(echo "$free_mem_gb < $threshold" | bc -l) )); then     echo "Free memory is less than 2GB ($free_mem_gb GB). Restarting Apache..." #    restart some service here #    sudo systemctl restart apache2 else     echo "Free memory is sufficient: $free_mem_gb GB." fi