集群

【Cluster】

源代码: lib/cluster.js

可以使用 Node.js 进程群集来运行多个 Node.js 实例，从而在它们的应用线程之间分配工作负载。当不需要进程隔离时，可以改用 worker_threads 模块，该模块允许在单个 Node.js 实例中运行多个应用线程。

【Clusters of Node.js processes can be used to run multiple instances of Node.js that can distribute workloads among their application threads. When process isolation is not needed, use the worker_threads module instead, which allows running multiple application threads within a single Node.js instance.】

cluster 模块允许轻松创建共享服务器端口的子进程。

【The cluster module allows easy creation of child processes that all share server ports.】

import cluster from 'node:cluster';
import http from 'node:http';
import { cpus } from 'node:os';
import process from 'node:process';

const numCPUs = cpus().length;

if (cluster.isPrimary) {
  console.log(`Primary ${process.pid} is running`);

  // Fork workers.
  for (let i = 0; i < numCPUs; i++) {
    cluster.fork();
  }

  cluster.on('exit', (worker, code, signal) => {
    console.log(`worker ${worker.process.pid} died`);
  });
} else {
  // Workers can share any TCP connection
  // In this case it is an HTTP server
  http.createServer((req, res) => {
    res.writeHead(200);
    res.end('hello world\n');
  }).listen(8000);

  console.log(`Worker ${process.pid} started`);
}const cluster = require('node:cluster');
const http = require('node:http');
const numCPUs = require('node:os').cpus().length;
const process = require('node:process');

if (cluster.isPrimary) {
  console.log(`Primary ${process.pid} is running`);

  // Fork workers.
  for (let i = 0; i < numCPUs; i++) {
    cluster.fork();
  }

  cluster.on('exit', (worker, code, signal) => {
    console.log(`worker ${worker.process.pid} died`);
  });
} else {
  // Workers can share any TCP connection
  // In this case it is an HTTP server
  http.createServer((req, res) => {
    res.writeHead(200);
    res.end('hello world\n');
  }).listen(8000);

  console.log(`Worker ${process.pid} started`);
}拷贝

运行 Node.js 现在将在工作进程之间共享端口 8000：

【Running Node.js will now share port 8000 between the workers:】

$ node server.js
Primary 3596 is running
Worker 4324 started
Worker 4520 started
Worker 6056 started
Worker 5644 started 拷贝

在 Windows 上，还不能在工作进程中设置命名管道服务器。

【On Windows, it is not yet possible to set up a named pipe server in a worker.】