stress.js

function stress (fn /*, n */) {
  var n = arguments[1] || 1000,
      i, t,
      s = new Date();
  for (i = 0; i < n; i++) {
    fn();
  };
  t = ((new Date()) - s);
  return {
    handler: fn,
    total:   t,
    each:    t / n
  };
}