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|
(* Example: Create a number of processes and join them *)
open Printf
let square k =
(* a process body squaring an int *)
let r = k * k in
printf "process: square(%d)=%d\n%!" k r;
r
let fork_square, join_square = Netmcore_process.def_process square
let compute _ =
(* a process body that is kind of a main program for our computation *)
(* start a few processes... *)
let processes =
List.map
(fun k ->
let `Process pid = Netmcore_process.start fork_square k in
printf "start(%d): pid=%d\n%!" k pid;
`Process pid
)
[ 1; 2; 3; 4; 5; 6; 7; 8; 9; 10 ] in
(* and join them, adding up the results *)
let r =
List.fold_left
(fun acc pid ->
match Netmcore_process.join join_square pid with
| None ->
failwith "no result from process"
| Some sq ->
acc + sq
)
0
processes in
r
let fork_compute, join_compute = Netmcore_process.def_process compute
let () =
(* Netmcore.Debug.enable := true; *)
(* Netplex_controller.Debug.enable := true; *)
(* Netlog.Debug.enable_module "Netplex_controller"; *)
(* Netplex_container.Debug.enable := true; *)
let r =
Netmcore.run
~socket_directory:"run_create_join"
~first_process:(fun () -> Netmcore_process.start fork_compute ())
~extract_result:(fun ctrl pid ->
(* NB. We cannot use {!Netmcore_process.join} here,
because we are running in the master process. However,
we know that the first process is already finished,
and so [join_nowait] is sufficient.
*)
match Netmcore_process.join_nowait join_compute pid with
| None ->
failwith "no result"
| Some r ->
r
)
() in
printf "Final result: %d\n%!" r;
()
|
