Testing setInterval

The code is understand the behavior of setInterval in JavaScript

by bhatnagar018

HTML

<button onclick="foo()">
  Click Me !
</button>

JavaScript

var _id, __id;
(function() {
  console.clear();
  var i = j = 0;
  __id = setInterval(__count, 500);
  _id = setInterval(_count, 1000);

  function _count() {
    i++;
    console.log('1000 - ' + (i) + ' Time ' + Number(new Date()));
    if (i === 10) {
      clearInterval(_id);
    }
  }

  function __count() {
    j++;
    console.log('500 - ' + (j) + (' Time ') + Number(new Date()));
    if (j === 10) {
      clearInterval(__id);
    }
  }
})();

function foo() {
  console.log(Number(new Date()));
  for (var _i = 0; _i < 9009000000; _i++) {

  }
  //clearInterval(_id);
  //clearInterval(__id);
  console.log(Number(new Date()));
}