Updated the files.

my-app/node_modules/piscina/benchmark/fixtures/add.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = ({ a, b }) => a + b;

my-app/node_modules/piscina/benchmark/simple-benchmark.js

@@ -0,0 +1,29 @@
+'use strict';
+const { Piscina } = require('..');
+const { resolve } = require('path');
+
+async function simpleBenchmark ({ duration = 10000 } = {}) {
+  const pool = new Piscina({ filename: resolve(__dirname, 'fixtures/add.js') });
+  let done = 0;
+
+  const results = [];
+  const start = process.hrtime.bigint();
+  while (pool.queueSize === 0) {
+    results.push(scheduleTasks());
+  }
+
+  async function scheduleTasks () {
+    while ((process.hrtime.bigint() - start) / 1_000_000n < duration) {
+      await pool.runTask({ a: 4, b: 6 });
+      done++;
+    }
+  }
+
+  await Promise.all(results);
+
+  return done / duration * 1e3;
+}
+
+simpleBenchmark().then((opsPerSecond) => {
+  console.log(`opsPerSecond: ${opsPerSecond}`);
+});