am/child.html

## child.html
<html>
<head></head>
<body>
  <p>Loaded Content</p>
  <script>
    (function(){
      var i, el = null,
        x = [];

      for (i = 0; i < 10000; i++) {
        el = document.createElement('div');
        el.innerHTML = 'node ' + i;
        document.body.appendChild(el);
      }
      x.push(new Array(1000000).join('x'));
    })()
  </script>
</body>
</html>

## parent.html
<html>
<head></head>
<body>
  <button onclick="loadGame()">Load</button>
  <button onclick="unloadGame()">Unload</button>
  <div class="loader"></div>
  <script>
    var loadGame, unloadGame;

    loadGame = function() {
      var iframe = document.createElement('iframe');
      iframe.className = 'loader--iframe';
      iframe.src = 'child.html';
      document.querySelector('.loader').appendChild(iframe);
    };
    unloadGame = function() {
      document.querySelector('.loader')
        .removeChild(document.querySelector('.loader--iframe'));
    };
 </script>
 </body>
 </html>

## run.sh
#!/bin/bash

python -m SimpleHTTPServer 5000
	<html>
	<head></head>
	<body>
	<p>Loaded Content</p>
	<script>
	(function(){
	var i, el = null,
	x = [];

	for (i = 0; i < 10000; i++) {
	el = document.createElement('div');
	el.innerHTML = 'node ' + i;
	document.body.appendChild(el);
	}
	x.push(new Array(1000000).join('x'));
	})()
	</script>
	</body>
	</html>