nav_timing.html

<!doctype html>
<html>
  <head>
  <title>Nav Timing Test Page</title>
  </head>
  <body>
<h1>Nav Timing Test Page</h1>
    <img src='https://raw.githubusercontent.com/bizzbyster/bizzbyster.github.io/master/images/zip-icon.png'>
    <script>
     var reqCount = 0;
    var myReq = new XMLHttpRequest();
    myReq.open('GET', url, true);
    myReq.onload = function(e) {
      window.performance.mark('mark_end_xhr');
      reqCnt++;
      window.performance.measure('measure_xhr_' + reqCnt, 'mark_start_xhr', 'mark_end_xhr');
      var items = window.performance.getEntriesByType('measure');
      for (var i = 0; i < items.length(); ++i) {
        var req = items[i];
        document.write('XHR ' + req.name + ' took ' + req.duration + 'ms');
      }
    }
    window.performance.mark('mark_start_xhr');
    myReq.send();
    
    </script>
  </body>
</html>