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> 7var sandbox = document.getElementById('sandbox'); 8var observing = false; 9 10var observer = new WebKitMutationObserver(listener); 11var tickledSpan = document.createElement('span'); 12observer.observe(tickledSpan, {attributes: true}); 13 14function resetState() { 15 window.start = null; 16 window.numRuns = 25; 17 window.times = []; 18} 19 20function runAgain() { 21 tickledSpan.setAttribute('data-foo', numRuns); 22} 23 24function hideFromObservation(func) { 25 if (observing) 26 observer.disconnect() 27 func(); 28 if (observing) 29 observer.observe(sandbox, {childList: true}); 30} 31 32function 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 60resetState(); 61PerfTestRunner.log('Running ' + numRuns + ' times without observation'); 62window.addEventListener('load', runAgain); 63</script> 64</body> 65