Node.js tester of dns lookup vs ip using the dns module

nodejs-dns-vs-ip-lookup-test.js

// This gist is helpful in determining if the dns resolution is the bottleneck when making
// outbound http request
var dns, http, util;
util = require('util');
dns = require('dns');

function outputMs()
{
  var d = new Date();
  var n = d.getUTCMilliseconds();
  return n;
}
// enter your ip and dns that you are comparing below
var iphost = '<enter IP here>';
var host = '<enter dns name here>';

util.log("start dns lookup ms:" + outputMs());
var startTime = outputMs();
dns.lookup(host, 4, function(err, address, family) {
  var totalTime = startTime - outputMs();
  return util.log("dns lookup took " + totalTime + 'ms:');

});

dns.resolve(host, function(err, address, family) {
  var totalTime = startTime - outputMs();
  return util.log("dns resolve took " + totalTime + 'ms:');
});


util.log("start lookup for ip ms:" + outputMs());
var startTime = outputMs();
dns.lookup(iphost, 4, function(err, address, family) {
  var totalTime = startTime - outputMs();
  return util.log("dns ip lookup took " + totalTime + 'ms:');

});

dns.resolve(iphost, function(err, address, family) {
  var totalTime = startTime - outputMs();
  return util.log("dns ip resolve took " + totalTime + 'ms:');
});

I've posted some more info of dns related problems and symptoms and updated code to: https://gist.github.com/gabrielf/7746695