got-690.js

const http = require('http')

const PORT = 8888
const REQUEST_LATENCY = 100
const REQUEST_COUNT = 1000

const requestOptions = {
  hostname: '127.0.0.1',
  port: PORT,
  path: '/',
  agent: new http.Agent({ keepAlive: true })
}

const reused = new Set()
const id = Symbol('id')
let idCount = 0

const makeRequests = cb => {
  let completedCount = 0
  for (let i = 0; i < REQUEST_COUNT; ++i) {
    http.request(requestOptions, res => {
      if (res.socket[id]) {
        reused.add(res.socket[id])
      } else {
        res.socket[id] = ++idCount
      }
      res.once('end', () => {
        // This supposedly causes a memory leak?
        res.setTimeout(0)
        if (++completedCount === REQUEST_COUNT) {
          cb()
        }
      }).resume()
    }).end()
  }
}

const server = http.createServer((_req, res) => {
  setTimeout(() => {
    res.end()
  }, REQUEST_LATENCY)
})

server.listen(PORT, () => {
  console.log('listening')
  makeRequests(() => {
    console.log('batch 1 complete')
    makeRequests(() => {
      console.log('batch 2 complete')
      console.log('reused sockets:', reused.size)
      server.close()
    })
  })
})