async.forEach vs. sync forEach (very lame)

bench.js

var async = require('async');
var fs = require('fs');


var files = [];

while(files.length < 100000) {
  files.push('/some/file' + files.length);
}

var queue = [];

var next = function() {
  if (queue.length) {
    queue.shift()();
  }
};

var benchSync = function() {
  var start = Date.now();
  var pending = 0;
  var finish = function() {
    if (!--pending) {
      console.log('SYNC:', Date.now() - start);
      next();
    }
  };

  files.forEach(function(path) {
    pending++;
    fs.stat(path, finish);
  });
};


var benchAsync = function() {
  var start = Date.now();
  var pending = 0;
  var finish = function() {
    if (!--pending) {
      console.log('ASYNC:', Date.now() - start);
      next();
    }
  };

  async.forEach(files, function(path) {
    pending++;
    fs.stat(path, finish);
  });
};

while(queue.length < 10) {
  queue.push(benchAsync);
  queue.push(benchSync);
}

next();

$ node test.js
ASYNC: 3401
SYNC: 3410
ASYNC: 3414
SYNC: 3433
ASYNC: 3395
SYNC: 3414
ASYNC: 3404
SYNC: 3391
ASYNC: 3420
SYNC: 3444