lockfile tester

bam.js

var resolve = require("path").resolve
var lock    = require("lockfile").lock

var FILE    = resolve(__dirname, "LOCKFILE")
var PID     = process.pid
var OPTIONS = {retries : 0}
var SCALE   = 16

var results = []
var running = SCALE
var timestamp

function getlock(id) {
  process.nextTick(function () {
    lock(FILE, OPTIONS, function (er) {
      results.push({
        pid    : PID,
        id     : id,
        locked : !er,
        delta  : process.hrtime(timestamp)
      })

      running--
      if (!running) process.send(results)
    })
  })
}

process.on("message", function (message) {
  if (message.code === "go") {
    timestamp = message.timestamp
    for (var i = 0; i < SCALE; i++) getlock(i)
  }
  else if (message.code === "done") {
    process.exit(0)
  }
})

process.send("ready")

master.js

var resolve = require("path").resolve
var fork = require("child_process").fork

var MODULE  = resolve(__dirname, "bam.js")
var SCALE   = 16
var STARTUP = process.hrtime()

var results  = []
var starting = SCALE
var finished = 0

var children = []

for (var i = 0; i < SCALE; i++) {
  children[i] = fork(MODULE)
  children[i].on("message", onMessage)
}

function onMessage(message) {
  if (message === "ready") {
    starting--
    if (!starting) go()
  }
  else {
    results = results.concat(message)

    finished++
    if (finished === SCALE) done()
  }
}

function go() {
  for (var j = 0; j < SCALE; j++) {
    children[j].send({code : "go", timestamp : STARTUP})
  }
}

function done() {
  var j
  for (j = 0; j < SCALE; j++) children[j].send({code : "done"})

  results.sort(function (a, b) { return a.delta[1] - b.delta[1] })

  for (j = 0; j < results.length; j++) {
    var result = results[j]
    console.log(
      "%s %s\t%s\t%s",
      result.locked ? "LOCK" : "    ",
      result.pid,
      result.id,
      result.delta[1]
    )
  }
}