diff --git a/queuenode.ml b/queuenode.ml
index 1bc8721..b32980b 100644
--- a/queuenode.ml
+++ b/queuenode.ml
@@ -61,6 +61,11 @@ let shoveller info =
 let queue_handler info n sexp =
   match Message.message_of_sexp sexp with
     | Message.Post (name, body, token) ->
+      lwt () =
+	if info.backlog > 1000 && info.waiters > 0
+	then Lwt_unix.yield ()
+	else return ()
+      in
       info.backlog <- info.backlog + 1;
       info.backlog_out (Some body);
       return ()