Use os.availableParallelism() instead of os.cpus().length (#5091)

* Use os.availableParallelism()

* trim CPU model

---------

Co-authored-by: David Michon <[email protected]>

Author: dmichon-msft

apps/heft/src/cli/HeftActionRunner.ts

@@ -195,7 +195,7 @@ export class HeftActionRunner {
     this._terminal = options.terminal;
     this._metricsCollector = options.metricsCollector;
 
-    const numberOfCores: number = os.cpus().length;
+    const numberOfCores: number = os.availableParallelism?.() ?? os.cpus().length;
 
     // If an explicit parallelism number wasn't provided, then choose a sensible
     // default.

apps/heft/src/metrics/MetricsCollector.ts

@@ -143,6 +143,8 @@ export class MetricsCollector {
 
     const { taskTotalExecutionMs } = filledPerformanceData;
 
+    const cpus: os.CpuInfo[] = os.cpus();
+
     const metricData: IMetricsData = {
       command: command,
       encounteredError: filledPerformanceData.encounteredError,
@@ -151,8 +153,10 @@ export class MetricsCollector {
       totalUptimeMs: process.uptime() * 1000,
       machineOs: process.platform,
       machineArch: process.arch,
-      machineCores: os.cpus().length,
-      machineProcessor: os.cpus()[0].model,
+      machineCores: cpus.length,
+      // The Node.js model is sometimes padded, for example:
+      // "AMD Ryzen 7 3700X 8-Core Processor
+      machineProcessor: cpus[0].model.trim(),
       machineTotalMemoryMB: os.totalmem(),
       commandParameters: parameters || {}
     };

common/changes/@microsoft/rush/available-parallelism_2025-01-30-01-01.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@microsoft/rush",
+      "comment": "Prefer `os.availableParallelism()` to `os.cpus().length`.",
+      "type": "none"
+    }
+  ],
+  "packageName": "@microsoft/rush"
+}

common/changes/@rushstack/heft/available-parallelism_2025-01-30-01-01.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/heft",
+      "comment": "Prefer `os.availableParallelism()` to `os.cpus().length`.",
+      "type": "patch"
+    }
+  ],
+  "packageName": "@rushstack/heft"
+}

common/changes/@rushstack/module-minifier/available-parallelism_2025-01-30-01-01.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/module-minifier",
+      "comment": "Prefer `os.availableParallelism()` to `os.cpus().length`.",
+      "type": "patch"
+    }
+  ],
+  "packageName": "@rushstack/module-minifier"
+}

common/changes/@rushstack/package-extractor/available-parallelism_2025-01-30-01-01.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/package-extractor",
+      "comment": "Prefer `os.availableParallelism()` to `os.cpus().length`.",
+      "type": "patch"
+    }
+  ],
+  "packageName": "@rushstack/package-extractor"
+}

common/changes/@rushstack/webpack4-module-minifier-plugin/available-parallelism_2025-01-30-01-01.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/webpack4-module-minifier-plugin",
+      "comment": "Prefer `os.availableParallelism()` to `os.cpus().length`.",
+      "type": "patch"
+    }
+  ],
+  "packageName": "@rushstack/webpack4-module-minifier-plugin"
+}

libraries/module-minifier/src/WorkerPoolMinifier.ts

@@ -2,7 +2,7 @@
 // See LICENSE in the project root for license information.
 
 import { createHash } from 'crypto';
-import { cpus } from 'os';
+import os from 'os';
 import type { ResourceLimits } from 'worker_threads';
 
 import serialize from 'serialize-javascript';
@@ -24,7 +24,7 @@ import type {
 export interface IWorkerPoolMinifierOptions {
   /**
    * Maximum number of worker threads to use. Will never use more than there are modules to process.
-   * Defaults to os.cpus().length
+   * Defaults to os.availableParallelism()
    */
   maxThreads?: number;
   /**
@@ -62,7 +62,7 @@ export class WorkerPoolMinifier implements IModuleMinifier {
 
   public constructor(options: IWorkerPoolMinifierOptions) {
     const {
-      maxThreads = cpus().length,
+      maxThreads = os.availableParallelism?.() ?? os.cpus().length,
       terserOptions = {},
       verbose = false,
       workerResourceLimits

libraries/package-extractor/src/scripts/createLinks/utilities/constants.ts

@@ -8,7 +8,7 @@ import type { TARGET_ROOT_SCRIPT_RELATIVE_PATH_TEMPLATE_STRING as TargetRootScri
 /**
  * The maximum number of concurrent operations to perform.
  */
-export const MAX_CONCURRENCY: number = os.cpus().length * 2;
+export const MAX_CONCURRENCY: number = (os.availableParallelism?.() ?? os.cpus().length) * 2;
 
 /**
  * The name of the action to create symlinks.

libraries/rush-lib/src/cli/parsing/ParseParallelism.ts

@@ -9,7 +9,7 @@ import * as os from 'os';
  */
 export function parseParallelism(
   rawParallelism: string | undefined,
-  numberOfCores: number = os.cpus().length
+  numberOfCores: number = os.availableParallelism?.() ?? os.cpus().length
 ): number {
   if (rawParallelism) {
     if (rawParallelism === 'max') {