深入浅析Node中的进程和线程

// app.js
const Koa = require('koa')
const router = require('koa-router')()
const app = new Koa()

// 用来测试是否被阻塞
router.get('/test', (ctx) => {
    ctx.body = {
        pid: process.pid,
        msg: 'Hello World'
    }
})
router.get('/fibo', (ctx) => {
    const { num = 38 } = ctx.query
    const start = Date.now()
    // 斐波那契数列
    const fibo = (n) => {
        return n > 1 ? fibo(n - 1) + fibo(n - 2) : 1
    }
    fibo(num)

    ctx.body = {
        pid: process.pid,
        duration: Date.now() - start
    }
})

app.use(router.routes())
app.listen(9000, () => {
    console.log('Server is running on 9000')
})

// axios.js
const axios = require('axios')

const start = Date.now()
const fn = (url) => {
    axios.get(`Http://127.0.0.1:9000/${ url }`).then((res) => {
        console.log(res.data, `耗时: ${ Date.now() - start }ms`)
    })
}

fn('test')
fn('fibo?num=43')
fn('test')

// app.js
const Koa = require('koa')
const router = require('koa-router')()
const { Worker } = require('worker_threads')
const app = new Koa()

// 用来测试是否被阻塞
router.get('/test', (ctx) => {
    ctx.body = {
        pid: process.pid,
        msg: 'Hello World'
    }
})
router.get('/fibo', async (ctx) => {
    const { num = 38 } = ctx.query
    ctx.body = await asyncFibo(num)
})

const asyncFibo = (num) => {
    return new Promise((resolve, reject) => {
        // 创建 worker 线程并传递数据
        const worker = new Worker('./fibo.js', { workerData: { num } })
        // 主线程监听子线程发送的消息
        worker.on('message', resolve)
        worker.on('error', reject)
        worker.on('exit', (code) => {
            if (code !== 0) reject(new Error(`Worker stopped with exit code ${code}`))
        })
    })
}

app.use(router.routes())
app.listen(9000, () => {
    console.log('Server is running on 9000')
})

const { workerData, parentPort } = require('worker_threads')
const { num } = workerData

const start = Date.now()
// 斐波那契数列
const fibo = (n) => {
    return n > 1 ? fibo(n - 1) + fibo(n - 2) : 1
}
fibo(num)

parentPort.postMessage({
    pid: process.pid,
    duration: Date.now() - start
})

// fibo-10.js
const axios = require('axios')

const url = `http://127.0.0.1:9000/fibo?num=38`
const start = Date.now()

for (let i = 0; i < 10; i++) {
    axios.get(url).then((res) => {
        console.log(res.data, `耗时: ${ Date.now() - start }ms`)
    })
}

// app.js
const cluster = require('cluster')
const http = require('http')
const numCPUs = require('os').cpus().length
// const numCPUs = 10 // worker 进程的数量一般和 CPU 核心数相同
const Koa = require('koa')
const router = require('koa-router')()
const app = new Koa()

// 用来测试是否被阻塞
router.get('/test', (ctx) => {
    ctx.body = {
        pid: process.pid,
        msg: 'Hello World'
    }
})
router.get('/fibo', (ctx) => {
    const { num = 38 } = ctx.query
    const start = Date.now()
    // 斐波那契数列
    const fibo = (n) => {
        return n > 1 ? fibo(n - 1) + fibo(n - 2) : 1
    }
    fibo(num)

    ctx.body = {
        pid: process.pid,
        duration: Date.now() - start
    }
})
app.use(router.routes())

if (cluster.isMaster) {
    console.log(`Master ${process.pid} is running`)
    
    // 衍生 worker 进程
    for (let i = 0; i < numCPUs; i++) {
        cluster.fork()
    }

    cluster.on('exit', (worker, code, signal) => {
        console.log(`worker ${worker.process.pid} died`)
    })
} else {
    app.listen(9000)
    console.log(`Worker ${process.pid} started`)
}