A quick (hacky) Chef recipe for adding noatime and a swap file in case a swap file does not exist

chef-swap.rb

# Create and enable a swap file

have_file_swap = false

File.open('/etc/fstab',"r") do |fstab|
  fstab.each do |line|
    # Tokenize each fstab line with a space separator
    tokens = line.split
    if tokens[2] == "swap" && tokens[0] !~ /\/dev/
      have_file_swap = true
      next
    end
  end
end

# Create a regular swap file in case there is none

unless have_file_swap
  swap_size = 2048
  Chef::Log.info("Swapfile not found. Manually creating one of #{swap_size}M for OOM safety")

  execute "creating swapfile" do
    command "/bin/dd if=/dev/zero of=/swap.img bs=1M count=#{swap_size}"
    action :run
    creates "/swap.img"
  end

  execute "formatting swapfile" do
    command "/sbin/mkswap -L local /swap.img"
    action :run
  end

  mount "none" do
    device "/swap.img"
    fstype "swap"
    options [ "sw"]
    dump 0
    pass 0
    action :enable
  end

  execute "mounting swapfile" do
    command "/sbin/swapon -a"
    action :run
  end

end