diff --git a/ocaml/libs/http-lib/http_svr.ml b/ocaml/libs/http-lib/http_svr.ml
index 3c8ec7facbb..54a8b96ba73 100644
--- a/ocaml/libs/http-lib/http_svr.ml
+++ b/ocaml/libs/http-lib/http_svr.ml
@@ -648,7 +648,7 @@ let start ?header_read_timeout ?header_total_timeout ?max_header_length
     ; body=
         handle_connection ~header_read_timeout ~header_total_timeout
           ~max_header_length x
-    ; lock= Xapi_stdext_threads.Semaphore.create conn_limit
+    ; lock= Semaphore.Counting.make conn_limit
     }
   in
   let server = Server_io.server handler socket in
diff --git a/ocaml/libs/http-lib/server_io.ml b/ocaml/libs/http-lib/server_io.ml
index 09abf253ee1..c821a27c024 100644
--- a/ocaml/libs/http-lib/server_io.ml
+++ b/ocaml/libs/http-lib/server_io.ml
@@ -23,7 +23,7 @@ type handler = {
     name: string
   ; (* body should close the provided fd *)
     body: Unix.sockaddr -> Unix.file_descr -> unit
-  ; lock: Xapi_stdext_threads.Semaphore.t
+  ; lock: Semaphore.Counting.t
 }
 
 let handler_by_thread (h : handler) (s : Unix.file_descr)
@@ -31,7 +31,7 @@ let handler_by_thread (h : handler) (s : Unix.file_descr)
   Thread.create
     (fun () ->
       Fun.protect
-        ~finally:(fun () -> Xapi_stdext_threads.Semaphore.release h.lock 1)
+        ~finally:(fun () -> Semaphore.Counting.release h.lock)
         (Debug.with_thread_named h.name (fun () -> h.body caller s))
     )
     ()
@@ -49,7 +49,7 @@ let establish_server ?(signal_fds = []) forker handler sock =
       @@ Polly.wait epoll 2 (-1) (fun _ fd _ ->
              (* If any of the signal_fd is active then bail out *)
              if List.mem fd signal_fds then raise PleaseClose ;
-             Xapi_stdext_threads.Semaphore.acquire handler.lock 1 ;
+             Semaphore.Counting.acquire handler.lock ;
              let s, caller = Unix.accept ~cloexec:true sock in
              try ignore (forker handler s caller)
              with exc ->
diff --git a/ocaml/libs/http-lib/server_io.mli b/ocaml/libs/http-lib/server_io.mli
index 3aca0234743..3c52f53a804 100644
--- a/ocaml/libs/http-lib/server_io.mli
+++ b/ocaml/libs/http-lib/server_io.mli
@@ -16,7 +16,7 @@ type handler = {
     name: string  (** used for naming the thread *)
   ; body: Unix.sockaddr -> Unix.file_descr -> unit
         (** function called in a thread for each connection*)
-  ; lock: Xapi_stdext_threads.Semaphore.t
+  ; lock: Semaphore.Counting.t
 }
 
 type server = {
diff --git a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/semaphore.ml b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/semaphore.ml
deleted file mode 100644
index 06621049c91..00000000000
--- a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/semaphore.ml
+++ /dev/null
@@ -1,57 +0,0 @@
-(*
- * Copyright (C) Citrix Systems Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published
- * by the Free Software Foundation; version 2.1 only. with the special
- * exception on linking described in file LICENSE.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser General Public License for more details.
- *)
-
-type t = {mutable n: int; m: Mutex.t; c: Condition.t}
-
-let create n =
-  if n <= 0 then
-    invalid_arg (Printf.sprintf "Semaphore value must be positive, got %d" n) ;
-  let m = Mutex.create () and c = Condition.create () in
-  {n; m; c}
-
-exception Inconsistent_state of string
-
-let inconsistent_state fmt =
-  Printf.ksprintf (fun msg -> raise (Inconsistent_state msg)) fmt
-
-let acquire s k =
-  if k <= 0 then
-    invalid_arg
-      (Printf.sprintf "Semaphore acquisition requires a positive value, got %d"
-         k
-      ) ;
-  Mutex.lock s.m ;
-  while s.n < k do
-    Condition.wait s.c s.m
-  done ;
-  if not (s.n >= k) then
-    inconsistent_state "Semaphore value cannot be smaller than %d, got %d" k s.n ;
-  s.n <- s.n - k ;
-  Condition.signal s.c ;
-  Mutex.unlock s.m
-
-let release s k =
-  if k <= 0 then
-    invalid_arg
-      (Printf.sprintf "Semaphore release requires a positive value, got %d" k) ;
-  Mutex.lock s.m ;
-  s.n <- s.n + k ;
-  Condition.signal s.c ;
-  Mutex.unlock s.m
-
-let execute_with_weight s k f =
-  acquire s k ;
-  Xapi_stdext_pervasives.Pervasiveext.finally f (fun () -> release s k)
-
-let execute s f = execute_with_weight s 1 f
diff --git a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/semaphore.mli b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/semaphore.mli
deleted file mode 100644
index 207e612032d..00000000000
--- a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/semaphore.mli
+++ /dev/null
@@ -1,40 +0,0 @@
-(*
- * Copyright (C) Citrix Systems Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published
- * by the Free Software Foundation; version 2.1 only. with the special
- * exception on linking described in file LICENSE.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser General Public License for more details.
- *)
-
-type t
-
-exception Inconsistent_state of string
-
-val create : int -> t
-(** [create n] create a semaphore with initial value [n] (a positive integer).
-    Raise {!Invalid_argument} if [n] <= 0 *)
-
-val acquire : t -> int -> unit
-(** [acquire k s] block until the semaphore value is >= [k] (a positive integer),
-    then atomically decrement the semaphore value by [k].
-    Raise {!Invalid_argument} if [k] <= 0 *)
-
-val release : t -> int -> unit
-(** [release k s] atomically increment the semaphore value by [k] (a positive
-    integer).
-    Raise {!Invalid_argument} if [k] <= 0 *)
-
-val execute_with_weight : t -> int -> (unit -> 'a) -> 'a
-(** [execute_with_weight s k f] {!acquire} the semaphore with [k],
-    then run [f ()], and finally {!release} the semaphore with the same value [k]
-    (even in case of failure in the execution of [f]).
-    Return the value of [f ()] or re-raise the exception if any. *)
-
-val execute : t -> (unit -> 'a) -> 'a
-(** [execute s f] same as [{execute_with_weight} s 1 f] *)
diff --git a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml
index 1ca5e916ef4..311d985ca69 100644
--- a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml
+++ b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml
@@ -14,11 +14,20 @@
 
 module M = Mutex
 
+let finally = Xapi_stdext_pervasives.Pervasiveext.finally
+
 module Mutex = struct
   (** execute the function f with the mutex hold *)
   let execute lock f =
     Mutex.lock lock ;
-    Xapi_stdext_pervasives.Pervasiveext.finally f (fun () -> Mutex.unlock lock)
+    finally f (fun () -> Mutex.unlock lock)
+end
+
+module Semaphore = struct
+  let execute s f =
+    let module Semaphore = Semaphore.Counting in
+    Semaphore.acquire s ;
+    finally f (fun () -> Semaphore.release s)
 end
 
 (** Parallel List.iter. Remembers all exceptions and returns an association list mapping input x to an exception.
@@ -60,7 +69,6 @@ module Delay = struct
   exception Pre_signalled
 
   let wait (x : t) (seconds : float) =
-    let finally = Xapi_stdext_pervasives.Pervasiveext.finally in
     let to_close = ref [] in
     let close' fd =
       if List.mem fd !to_close then Unix.close fd ;
diff --git a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.mli b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.mli
index 057aedfa700..b5edcff21b8 100644
--- a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.mli
+++ b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.mli
@@ -15,6 +15,10 @@ module Mutex : sig
   val execute : Mutex.t -> (unit -> 'a) -> 'a
 end
 
+module Semaphore : sig
+  val execute : Semaphore.Counting.t -> (unit -> 'a) -> 'a
+end
+
 val thread_iter_all_exns : ('a -> unit) -> 'a list -> ('a * exn) list
 
 val thread_iter : ('a -> unit) -> 'a list -> unit
diff --git a/ocaml/networkd/lib/network_utils.ml b/ocaml/networkd/lib/network_utils.ml
index 39417cf1177..4a473b29579 100644
--- a/ocaml/networkd/lib/network_utils.ml
+++ b/ocaml/networkd/lib/network_utils.ml
@@ -1197,12 +1197,13 @@ module Ovs = struct
 
     val appctl : ?log:bool -> string list -> string
   end = struct
-    module Semaphore = Xapi_stdext_threads.Semaphore
+    module Semaphore = Semaphore.Counting
 
-    let s = Semaphore.create 5
+    let s = Semaphore.make 5
 
     let vsctl ?log args =
-      Semaphore.execute s (fun () ->
+      let execute = Xapi_stdext_threads.Threadext.Semaphore.execute in
+      execute s (fun () ->
           call_script ~on_error:error_handler ?log ovs_vsctl
             ("--timeout=20" :: args)
       )
diff --git a/ocaml/xapi-aux/throttle.ml b/ocaml/xapi-aux/throttle.ml
index 7be2ac9bd48..a9dacf7f164 100644
--- a/ocaml/xapi-aux/throttle.ml
+++ b/ocaml/xapi-aux/throttle.ml
@@ -17,10 +17,12 @@ module type SIZE = sig
 end
 
 module Make (Size : SIZE) = struct
-  module Semaphore = Xapi_stdext_threads.Semaphore
+  module Semaphore = Semaphore.Counting
 
   let with_lock = Xapi_stdext_threads.Threadext.Mutex.execute
 
+  let execute = Xapi_stdext_threads.Threadext.Semaphore.execute
+
   let semaphore = ref None
 
   let m = Mutex.create ()
@@ -29,11 +31,11 @@ module Make (Size : SIZE) = struct
     with_lock m @@ fun () ->
     match !semaphore with
     | None ->
-        let result = Semaphore.create (Size.n ()) in
+        let result = Semaphore.make (Size.n ()) in
         semaphore := Some result ;
         result
     | Some s ->
         s
 
-  let execute f = Semaphore.execute (get_semaphore ()) f
+  let execute f = execute (get_semaphore ()) f
 end
diff --git a/ocaml/xapi/xapi_sr.ml b/ocaml/xapi/xapi_sr.ml
index d572660e72d..7a83493b2de 100644
--- a/ocaml/xapi/xapi_sr.ml
+++ b/ocaml/xapi/xapi_sr.ml
@@ -20,7 +20,6 @@ module Rrdd = Rrd_client.Client
 let with_lock = Xapi_stdext_threads.Threadext.Mutex.execute
 
 module Listext = Xapi_stdext_std.Listext
-module Semaphore = Xapi_stdext_threads.Semaphore
 module Unixext = Xapi_stdext_unix.Unixext
 
 let finally = Xapi_stdext_pervasives.Pervasiveext.finally