PerformanceTests/Mutation/remove-child.html

   1 <!DOCTYPE html>
   2 <body>
   3 <pre id="log"></pre>
   4 <script src="../resources/runner.js"></script>
   5 <div id="sandbox" style="display:none"></div>
   6 <script>
   7 var sandbox = document.getElementById('sandbox');
   8 var observing = false;
   9
  10 var observer = new WebKitMutationObserver(listener);
  11 var tickledSpan = document.createElement('span');
  12 observer.observe(tickledSpan, {attributes: true});
  13
  14 function resetState() {
  15     window.start = null;
  16     window.numRuns = 25;
  17     window.times = [];
  18 }
  19
  20 function runAgain() {
  21     tickledSpan.setAttribute('data-foo', numRuns);
  22 }
  23
  24 function hideFromObservation(func) {
  25     if (observing)
  26         observer.disconnect()
  27     func();
  28     if (observing)
  29         observer.observe(sandbox, {childList: true});
  30 }
  31
  32 function listener(mutations) {
  33     if (start) {
  34         var time = Date.now() - start;
  35         times.push(time);
  36         PerfTestRunner.log(time);
  37     }
  38     if (numRuns-- >= 0) {
  39         runAgain();
  40         hideFromObservation(function() {
  41             for (var i = 0; i < 50000; ++i)
  42                 sandbox.appendChild(document.createElement('div'));
  43         });
  44         start = Date.now();
  45         while (sandbox.firstChild)
  46             sandbox.removeChild(sandbox.firstChild);
  47     } else {
  48         PerfTestRunner.logStatistics(times);
  49         if (!observing) {
  50             observer.observe(sandbox, {childList: true});
  51             observing = true;
  52             resetState();
  53             PerfTestRunner.log('\n------------\n');
  54             PerfTestRunner.log('Running ' + numRuns + ' times with observation');
  55             setTimeout(runAgain, 0);
  56         }
  57     }
  58 }
  59
  60 resetState();
  61 PerfTestRunner.log('Running ' + numRuns + ' times without observation');
  62 window.addEventListener('load', runAgain);
  63 </script>
  64 </body>