alarm: 30min_ram_swapped_out
      on: system.swapio
  lookup: sum -30m unaligned absolute of out
          # we have to convert KB to MB by dividing $this (i.e. the result of the lookup) with 1024
    calc: $this / 1024 * 100 / ( $system.ram.used + $system.ram.cached + $system.ram.free )
   every: 1m
    warn: $this > 1
    crit: $this > 10
   units: % of RAM
    info: the sum of all memory swapped out during the last 30 minutes, as a percentage of the available RAM

   alarm: pcent_of_ram_in_swap
      on: system.swap
    calc: $used * 100 / ( $system.ram.used + $system.ram.cached + $system.ram.free )
   every: 10s
    warn: $this > 10
    crit: $this > 50
   units: % of RAM
    info: the currently used swap space, as a percentage of the available RAM