benchmark: conditionally use spawn with taskset for cpu pinning

This change enhances the benchmarking tool by conditionally using the,
spawn method with taskset for CPU pinning, improving consistency of
benchmark results across different environments.

Fixes: nodejs#52233

benchmark/compare.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const { fork } = require('child_process');
+const { spawn, fork } = require('child_process');
 const { inspect } = require('util');
 const path = require('path');
 const CLI = require('./_cli.js');
@@ -40,6 +40,12 @@ if (benchmarks.length === 0) {
   return;
 }
 
+const cpuCoreSetting = cli.optional.set.find(s => s.startsWith('CPUCORE='));
+let cpuCore = null;
+if (cpuCoreSetting) {
+  cpuCore = cpuCoreSetting.split('=')[1];
+}
+
 // Create queue from the benchmarks list such both node versions are tested
 // `runs` amount of times each.
 // Note: BenchmarkProgress relies on this order to estimate
@@ -70,9 +76,23 @@ if (showProgress) {
 (function recursive(i) {
   const job = queue[i];
 
-  const child = fork(path.resolve(__dirname, job.filename), cli.optional.set, {
-    execPath: cli.optional[job.binary],
-  });
+  const resolvedPath = path.resolve(__dirname, job.filename);
+  let child;
+  if (cpuCore !== null) {
+    const spawnArgs = ['-c', cpuCore, cli.optional[job.binary], resolvedPath, ...cli.optional.set];
+    child = spawn('taskset', spawnArgs, {
+      env: process.env,
+      stdio: ['inherit', 'pipe', 'ipc'],
+    });
+
+    child.stdout.on('data', (data) => {
+      process.stdout.write(data);
+    });
+  } else {
+    child = fork(resolvedPath, cli.optional.set, {
+      execPath: cli.optional[job.binary],
+    });
+  }
 
   child.on('message', (data) => {
     if (data.type === 'report') {

benchmark/run.js

@@ -1,7 +1,7 @@
 'use strict';
 
 const path = require('path');
-const fork = require('child_process').fork;
+const { spawn, fork } = require('child_process');
 const CLI = require('./_cli.js');
 
 const cli = new CLI(`usage: ./node run.js [options] [--] <category> ...
@@ -34,16 +34,37 @@ if (!validFormats.includes(format)) {
   return;
 }
 
+const cpuCoreSetting = cli.optional.set.find(s => s.startsWith('CPUCORE='));
+let cpuCore = null;
+if (cpuCoreSetting) {
+  cpuCore = cpuCoreSetting.split('=')[1];
+}
+
 if (format === 'csv') {
   console.log('"filename", "configuration", "rate", "time"');
 }
 
 (function recursive(i) {
   const filename = benchmarks[i];
-  const child = fork(
-    path.resolve(__dirname, filename),
-    cli.test ? ['--test'] : cli.optional.set,
-  );
+  const scriptPath = path.resolve(__dirname, filename);
+  const args = cli.test ? ['--test'] : cli.optional.set;
+
+  let child;
+
+  if (cpuCore !== null) {
+    child = spawn('taskset', [`-c`, cpuCore, `node`, scriptPath, ...args], {
+      stdio: ['inherit', 'pipe', 'ipc']
+    });
+
+    child.stdout.on('data', (data) => {
+      process.stdout.write(data);
+    });
+  } else {
+    child = fork(
+      scriptPath,
+      args,
+    );
+  }
 
   if (format !== 'csv') {
     console.log();