$(document).ready(function () {
        var onScroll = function () {
          var scrollTop = $(this).scrollTop();
          console.log(google_ad_iframe_parent)
          google_ad_iframe.style.position = "relative"
          google_ad_iframe.style.top = scrollTop - $elem.offset().top + "px"
        };
        onScroll.apply(window);
        $(window).on('scroll', onScroll);
      });

above is the code for achieving parallax effect. what can I do remove the stuttering. is this because of all the calculation on every pixel change ?