css_animations_simultaneous_by_updating_class.html

<!DOCTYPE html>
<meta name="viewport" content="width=device-width, user-scalable=no">
<link rel="stylesheet" type="text/css" href="resources/animation.css">
<link rel="stylesheet" type="text/css" href="resources/tablet.css">
<script src="resources/perf_test_helper.js"></script>

<container id="container"></container>

<script>
var N = PerfTestHelper.getN(1000);
var duration = 1000;

for (var i = 0; i < N; i++) {
  var target = document.createElement('target');
  container.appendChild(target);
}

function startAllAnimations() {
  for (var i = 0; i < container.childNodes.length; i++) {
    container.childNodes[i].classList.toggle('reverse');
  }
}
startAllAnimations();
setInterval(startAllAnimations, duration);

PerfTestHelper.signalReady();
</script>

chromium/tools/perf/page_sets/tough_animation_cases/css_animations_simultaneous_by_updating_class.html