Performance tunning about learning HOT 2 OPEN

function onScroll (evt) {

  // Store the scroll value for laterz.
  lastScrollY = window.scrollY;

  // Prevent multiple rAF callbacks.
  if (scheduledAnimationFrame)
    return;

  scheduledAnimationFrame = true;
  requestAnimationFrame(readAndUpdatePage);
}
window.addEventListener('scroll', onScroll);

function processTaskList(taskStartTime) {
  var taskFinishTime;

  do {
    // Assume the next task is pushed onto a stack.
    var nextTask = taskList.pop();

    // Process nextTask.
    processTask(nextTask);

    // Go again if there’s enough time to do the next task.
    taskFinishTime = window.performance.now();
  } while (taskFinishTime - taskStartTime < 3);

  if (taskList.length > 0)
    requestAnimationFrame(processTaskList);
}

var textContent = `
	onmessage = function(oEvent){
        importScripts()
     }
`
var blob = new Blob([textContent], {type: 'text/javascript'})
var worker = new Worker(window.URL.createObjectURL(blob));
worker.postMessage("Hello2")