1 files changed, 12 insertions, 2 deletions
diff --git a/ext/node/benchmarks/child_process_ipc.mjs b/ext/node/benchmarks/child_process_ipc.mjs
index 0486972dc..39377cd8c 100644
--- a/ext/node/benchmarks/child_process_ipc.mjs
+++ b/ext/node/benchmarks/child_process_ipc.mjs
@@ -5,10 +5,20 @@ import { setImmediate } from "node:timers";
 if (process.env.CHILD) {
   const len = +process.env.CHILD;
   const msg = ".".repeat(len);
+  let waiting = false;
   const send = () => {
-    while (process.send(msg));
+    while (
+      process.send(msg, undefined, undefined, (_e) => {
+        if (waiting) {
+          waiting = false;
+          setImmediate(send);
+        }
+      })
+    );
     // Wait: backlog of unsent messages exceeds threshold
-    setImmediate(send);
+    // once the message is sent, the callback will be called
+    // and we'll resume
+    waiting = true;
   };
   send();
 } else {