darkening.ml

let table = Array.init 10_000 (fun _ -> Bytes.make 1_000 'a')

let writes =
  Option.map bool_of_string (Sys.getenv_opt "WRITES")
  |> Option.value ~default:false

let[@inline never] f () =
  List.init (Array.length table) (fun i ->
    let buf = table.(i) in
    if writes then table.(i) <- buf;
    Bytes.get buf 42)

let () =
  for i = 1 to 10_000 do
    ignore (Sys.opaque_identity (f ()))
  done;
  let stat = Gc.quick_stat () in
  Printf.printf "%15s: %b\n%15s: %.0f\n%15s: %.0f\n%15s: %d\n%15s: %d\n"
    "writes" writes
    "minor_words" stat.minor_words
    "major_words" stat.major_words
    "cycles" stat.major_collections
    "heap_words" stat.top_heap_words