create_swap_file_if_not_exists.sh

if [ -f /swapfile ]; then
    echo "The Swap file already exists."
else
    sudo fallocate -l 4G /swapfile
    sudo chmod 600 /swapfile
    sudo mkswap /swapfile
    sudo swapon /swapfile
    sudo sh -c 'echo "/swapfile   none    swap    sw    0   0" >> /etc/fstab'
    sudo sh -c 'echo "vm.swappiness = 10" >> /etc/sysctl.conf' # 60 for desktops, closer to 0 for VPS (10?)
    sudo sh -c 'echo "vm.vfs_cache_pressure = 50" >> /etc/sysctl.conf'
    echo "The Swap file is created and added to '/etc/fstab' to make the changes permanent."
fi