add a 512MB swapfile

mk_new_swap

#!/bin/bash -e

# This script adds a 512MB swapfile to the system

function get_new_swapfile() {
  for i in `seq 0 99`; do
    if [ ! -e /swapfile.$i ]; then
      echo /swapfile.$i
      return
    fi
  done
  # Seriously? 100 swapfiles already exist?
  echo "too many swapfiles"
  exit 1
}

SWAPFILE=$(get_new_swapfile)

# if we have a race condition in the root directory, we have other problems
install -o root -g root -m 0600 /dev/null $SWAPFILE
dd if=/dev/zero of=$SWAPFILE bs=1k count=512k
mkswap $SWAPFILE
swapon $SWAPFILE
echo "$SWAPFILE swap swap auto 0 0" >> /etc/fstab