1 files changed, 36 insertions, 0 deletions
diff --git a/ocaml-binary-annot/testsuite/tests/lib-threads/token2.ml b/ocaml-binary-annot/testsuite/tests/lib-threads/token2.ml
new file mode 100644
index 0000000000..32f2c6ed37
--- /dev/null
+++ b/ocaml-binary-annot/testsuite/tests/lib-threads/token2.ml
@@ -0,0 +1,36 @@
+(* Performance test for I/O scheduling *)
+
+let mut = Mutex.create()
+
+let niter = ref 0
+
+let token = ref 0
+
+let process (n, ins, outs, nprocs) =
+  let buf = String.create 1 in
+  while true do
+    Unix.read ins.(n) buf 0 1;
+    (* Printf.printf "Thread %d got the token\n" n; *)
+    if n = 0 then begin
+      decr niter;
+      if !niter <= 0 then exit 0
+    end;
+    let next = if n + 1 >= nprocs then 0 else n + 1 in
+    (* Printf.printf "Thread %d sending token to thread %d\n" n next; *)
+    Unix.write outs.(next) buf 0 1
+  done
+
+let main() =
+  let nprocs = try int_of_string Sys.argv.(1) with _ -> 100 in
+  let iter = try int_of_string Sys.argv.(2) with _ -> 1000 in
+  let ins = Array.create nprocs Unix.stdin in
+  let outs = Array.create nprocs Unix.stdout in
+  for n = 0 to nprocs - 1 do
+    let (i, o) = Unix.pipe() in ins.(n) <- i; outs.(n) <- o
+  done;
+  niter := iter;
+  for i = 0 to nprocs - 1 do Thread.create process (i, ins, outs, nprocs) done;
+  Unix.write outs.(0) "X" 0 1;
+  Thread.delay 3600.
+
+let _ = main()