Make swap file

# All commands must be run as root except the final section.

fallocate -l 1G /swapfile   # 1 GB file
chmod 600 /swapfile         # root only read-write
mkswap /swapfile
#swapon /swapfile
echo "/swapfile none swap sw 0 0" >> /etc/fstab   # make sure it functions after reboot

mount -a
free -m   # make sure it is working now