From 96d8e9284ef6983f8e357d66da5d4c3c7086ab0c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?0hm=E2=98=98=EF=B8=8F?= <git8ankanroy@gmail.com>
Date: Sat, 19 Jul 2025 22:23:47 +0530
Subject: [PATCH 1/2] benchmark: new options setup and teardown

This commit introduces two new options to the Benchmark tool: setup
and teardown. The setup option runs before any forks are created,
and teardown executes after all forks have completed.
---
 benchmark/common.js                               |  7 +++++++
 .../writing-and-running-benchmarks.md             | 15 +++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/benchmark/common.js b/benchmark/common.js
index 0d3dbef24d07ad..a9c5e58183dafe 100644
--- a/benchmark/common.js
+++ b/benchmark/common.js
@@ -9,6 +9,8 @@ function allow() {
 
 class Benchmark {
   constructor(fn, configs, options = {}) {
+    this.setup = options.setup;
+    this.teardown = options.teardown;
     // Used to make sure a benchmark only start a timer once
     this._started = false;
 
@@ -62,6 +64,9 @@ class Benchmark {
       if (process.env.NODE_RUN_BENCHMARK_FN !== undefined) {
         fn(this.config);
       } else {
+        if (this.setup) {
+          this.setup();
+        }
         // _run will use fork() to create a new process for each configuration
         // combination.
         this._run();
@@ -234,6 +239,8 @@ class Benchmark {
 
         if (queueIndex + 1 < this.queue.length) {
           recursive(queueIndex + 1);
+        } else if (this.teardown) {
+          this.teardown();
         }
       });
     };
diff --git a/doc/contributing/writing-and-running-benchmarks.md b/doc/contributing/writing-and-running-benchmarks.md
index 2664116aefc4b3..1b32d869147c73 100644
--- a/doc/contributing/writing-and-running-benchmarks.md
+++ b/doc/contributing/writing-and-running-benchmarks.md
@@ -523,6 +523,14 @@ The arguments of `createBenchmark` are:
   Each configuration is a property with an array of possible values.
   The configuration values can only be strings or numbers.
 * `options` {Object} The benchmark options. Supported options:
+  * `setup` {Function} A function to be run once by the main "controller"
+    process before any benchmark child processes are spawned. Ideal for
+    preparing the environment for the entire benchmark suite.
+
+  * `teardown` {Function} A function to be run once by the main "controller"
+    process after all benchmark child processes have completed. Ideal for
+    cleaning up the environment.
+
   * `flags` {Array} Contains node-specific command line flags to pass to
     the child process.
 
@@ -585,6 +593,13 @@ const configs = {
 const options = {
   // Add --expose-internals in order to require internal modules in main
   flags: ['--zero-fill-buffers'],
+  // Setup and teardown functions are run in the parent process, once.
+  setup() {
+    console.log('Running setup.');
+  },
+  teardown() {
+    console.log('Running teardown.');
+  },
 };
 
 // `main` and `configs` are required, `options` is optional.

From 0bd0afc2ed864e54b72e02c5488499bdbcc586b1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?0hm=E2=98=98=EF=B8=8F?= <git8ankanroy@gmail.com>
Date: Sat, 19 Jul 2025 22:25:53 +0530
Subject: [PATCH 2/2] benchmark: updates to use the new setup and teardown
 options

---
 benchmark/module/module-require.js | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/benchmark/module/module-require.js b/benchmark/module/module-require.js
index 5346366dc8e8b7..62dee9c8b7f954 100644
--- a/benchmark/module/module-require.js
+++ b/benchmark/module/module-require.js
@@ -5,15 +5,22 @@ const common = require('../common.js');
 const tmpdir = require('../../test/common/tmpdir');
 const benchmarkDirectory = tmpdir.resolve('nodejs-benchmark-module');
 
+const t = 1e4;
+
 const bench = common.createBenchmark(main, {
   type: ['.js', '.json', 'dir'],
-  n: [1e4],
+  n: [t],
+}, {
+  setup() {
+    tmpdir.refresh();
+    createEntryPoint(t);
+  },
+  teardown() {
+    tmpdir.refresh();
+  },
 });
 
 function main({ type, n }) {
-  tmpdir.refresh();
-  createEntryPoint(n);
-
   switch (type) {
     case '.js':
       measureJSFile(n);
@@ -24,8 +31,6 @@ function main({ type, n }) {
     case 'dir':
       measureDir(n);
   }
-
-  tmpdir.refresh();
 }
 
 function measureJSFile(n) {