详解Node.js中单线程限制的有效解决方法

const cluster = require('cluster');
const http = require('http');
const numCPUs = require('os').cpus().length;

if (cluster.isMaster) {
  // 创建工作进程
  for (let i = 0; i < numCPUs; i++) {
    cluster.fork();
  }

  cluster.on('exit', (worker, code, signal) => {
    console.log(`工作进程 ${worker.process.pid} 已退出`);
  });
} else {
  // 工作进程可以共享同一个服务器端口
  http.createServer((req, res) => {
    res.writeHead(200);
    res.end('你好，世界\n');
  }).listen(8000);
}

const { fork } = require('child_process');

const compute = fork('compute.js');

compute.on('message', (result) => {
  console.log(`计算结果: ${result}`);
});

compute.send('开始计算');

process.on('message', (msg) => {
  if (msg === '开始计算') {
    // 执行 CPU 密集型任务
    let result = 0;
    for (let i = 0; i < 1e9; i++) {
      result += i;
    }
    process.send(result);
  }
});

const { Worker } = require('worker_threads');

const worker = new Worker(`
  const { parentPort } = require('worker_threads');
  let result = 0;
  for (let i = 0; i < 1e9; i++) {
    result += i;
  }
  parentPort.postMessage(result);
`, { eval: true });

worker.on('message', (result) => {
  console.log(`计算结果: ${result}`);
});

const fs = require('fs');

fs.readFile('example.txt', 'utf8', (err, data) => {
  if (err) {
    console.error('无法读取文件:', err);
    return;
  }
  console.log('文件内容:', data);
});

http {
  upstream nodejs_backend {
    server 127.0.0.1:3000;
    server 127.0.0.1:3001;
    server 127.0.0.1:3002;
    server 127.0.0.1:3003;
  }

  server {
    listen 80;

    location / {
      proxy_pass http://nodejs_backend;
      proxy_set_header Host $host;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header X-Forwarded-Proto $scheme;
    }
  }
}