copy_chan.ml

module C = Domainslib.Chan
let num_domains = try int_of_string Sys.argv.(1) with _ -> 4
let n = try int_of_string Sys.argv.(2) with _ -> 1024
let chunk_size = n / num_domains

let a = Array.make n 1.
let b = Array.create_float n

type message =
    Work of int * int
  | Quit

let rec create_work c start left =
  if left < chunk_size then begin
    C.send c (Work (start, start + left - 1));
    for _i = 1 to num_domains do
      C.send c Quit
    done
  end else begin
    C.send c (Work (start, start + chunk_size - 1));
    create_work c (start + chunk_size) (left - chunk_size)
  end  
;;

let part a b s e = Array.blit a s b s (e - s + 1)

let rec worker a b c =
  match C.recv c with
  | Work (s,e) ->
      part a b s e;
      worker a b c
  | Quit -> ()

let _ = 
  let c = C.make_bounded (num_domains + num_domains + 1) in
  create_work c 0 n;
  let domains =
    Array.init (num_domains - 1) (fun _ ->
      Domain.spawn (fun _ -> worker a b c))
  in
  worker a b c;
  Array.iter Domain.join domains