for setting up swapfiles on new VMs. do not use this script as is!

swappy.bash

#!/bin/bash
#
# SWAP
# ———the below command sequence is untested and should only be attempted/debuged————
# ———if you are frequently starting fresh VMs, too complicated and risky to have————
# ——————————————————————————————————————————————————————————————————————————————————
# ———i started creating this for an install script but quickly realized it's not————
# ———worth the effort and i'll end up screwing something up so.. saved here if i————
# ———ever end up deciding such an automation would be beneficial in the future——————
#
# proc_swap="$(cat /proc/swaps | sed -n 2p)"
# show_swapon="$(swapon --show)"
# total_swap="$(sed -n -E 's/.*SwapTotal:\s+([0-9]+).*/\1/p' /proc/meminfo)"
#
# if [[ -z $proc_swap && -z $show_swapon && $total_swap -eq 0 ]]; then
#     total_mem="$(free -b | sed -n -E 2p | sed -E 's/Mem:\s+([0-9]+)\s.*/\1/')"
#     vol_avail="$(df -lB 1 --output=avail / | tail +2)"
#
#     if [[ $vol_avail -gt $total_mem ]]; then
#         if [[ $(( $total_mem / 1000000 )) -ge 4000 ]]; then
#             swap_size=4000000000
#         elif [[ $(( $total_mem / 1000000 )) -lt 1200 ]]; then
#             swap_size=1000000000
#         else
#             swap_size=$total_mem
#         fi
#
#         fallocate -l $swap_size /swapfile
#         chmod 600 /swapfile
#         mkswap /swapfile
#         swapon /swapfile
#
#         swapon --show; free -h
#
#         cp /etc/fstab /etc/fstab.original
#         echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab
#     fi
# fi