lib: make queueMicrotask faster

No longer create an additional scope within queueMicrotask
in order to improve performance.

PR-URL: https://github.com/nodejs/node/pull/27032
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: James M Snell <jasnell@gmail.com>

2 files changed, 38 insertions, 0 deletions

diff --git a/benchmark/process/queue-microtask-breadth.js b/benchmark/process/queue-microtask-breadth.js
new file mode 100644
index 0000000000..8bb33f6fde
--- /dev/null
+++ b/benchmark/process/queue-microtask-breadth.js
@@ -0,0 +1,21 @@
+'use strict';
+
+const common = require('../common.js');
+const bench = common.createBenchmark(main, {
+  n: [4e5]
+});
+
+function main({ n }) {
+  var j = 0;
+
+  function cb() {
+    j++;
+    if (j === n)
+      bench.end(n);
+  }
+
+  bench.start();
+  for (var i = 0; i < n; i++) {
+    queueMicrotask(cb);
+  }
+}
diff --git a/benchmark/process/queue-microtask-depth.js b/benchmark/process/queue-microtask-depth.js
new file mode 100644
index 0000000000..407feb1b32
--- /dev/null
+++ b/benchmark/process/queue-microtask-depth.js
@@ -0,0 +1,17 @@
+'use strict';
+const common = require('../common.js');
+const bench = common.createBenchmark(main, {
+  n: [12e5]
+});
+
+function main({ n }) {
+  let counter = n;
+  bench.start();
+  queueMicrotask(onNextTick);
+  function onNextTick() {
+    if (--counter)
+      queueMicrotask(onNextTick);
+    else
+      bench.end(n);
+  }
+}