PageSpeed Insights có tối ưu toàn diện tốc độ tải Website

I. Tối ưu tốc độ website với PageSpeed Insights

PageSpeed Insights

Code Lazy Load Image

<script src='http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js' type='text/javascript'/>
<script>
//<![CDATA[
// Sticky Sidebar Decoded and lazy load
!function(i){i.fn.theiaStickySidebar=function(t){function e(t,e){var a=o(t,e);a||(console.log("TSS: Body width smaller than options.minWidth. Init is delayed."),i(document).on("scroll."+t.namespace,function(t,e){return function(a){var n=o(t,e);n&&i(this).unbind(a)}}(t,e)),i(window).on("resize."+t.namespace,function(t,e){return function(a){var n=o(t,e);n&&i(this).unbind(a)}}(t,e)))}function o(t,e){return t.initialized===!0||!(i("body").width()<t.minWidth)&&(a(t,e),!0)}function a(t,e){t.initialized=!0;var o=i("#theia-sticky-sidebar-stylesheet-"+t.namespace);0===o.length&&i("head").append(i('<style id="theia-sticky-sidebar-stylesheet-'+t.namespace+'">.theiaStickySidebar:after {content: ""; display: table; clear: both;}</style>')),e.each(function(){function e(){a.fixedScrollTop=0,a.sidebar.css({"min-height":"1px"}),a.stickySidebar.css({position:"static",width:"",transform:"none"})}function o(t){var e=t.height();return t.children().each(function(){e=Math.max(e,i(this).height())}),e}var a={};if(a.sidebar=i(this),a.options=t||{},a.container=i(a.options.containerSelector),0==a.container.length&&(a.container=a.sidebar.parent()),a.sidebar.parents().css("-webkit-transform","none"),a.sidebar.css({position:a.options.defaultPosition,overflow:"visible","-webkit-box-sizing":"border-box","-moz-box-sizing":"border-box","box-sizing":"border-box"}),a.stickySidebar=a.sidebar.find(".theiaStickySidebar"),0==a.stickySidebar.length){var s=/(?:text|application)\/(?:x-)?(?:javascript|ecmascript)/i;a.sidebar.find("script").filter(function(i,t){return 0===t.type.length||t.type.match(s)}).remove(),a.stickySidebar=i("<div>").addClass("theiaStickySidebar").append(a.sidebar.children()),a.sidebar.append(a.stickySidebar)}a.marginBottom=parseInt(a.sidebar.css("margin-bottom")),a.paddingTop=parseInt(a.sidebar.css("padding-top")),a.paddingBottom=parseInt(a.sidebar.css("padding-bottom"));var r=a.stickySidebar.offset().top,d=a.stickySidebar.outerHeight();a.stickySidebar.css("padding-top",1),a.stickySidebar.css("padding-bottom",1),r-=a.stickySidebar.offset().top,d=a.stickySidebar.outerHeight()-d-r,0==r?(a.stickySidebar.css("padding-top",0),a.stickySidebarPaddingTop=0):a.stickySidebarPaddingTop=1,0==d?(a.stickySidebar.css("padding-bottom",0),a.stickySidebarPaddingBottom=0):a.stickySidebarPaddingBottom=1,a.previousScrollTop=null,a.fixedScrollTop=0,e(),a.onScroll=function(a){if(a.stickySidebar.is(":visible")){if(i("body").width()<a.options.minWidth)return void e();if(a.options.disableOnResponsiveLayouts){var s=a.sidebar.outerWidth("none"==a.sidebar.css("float"));if(s+50>a.container.width())return void e()}var r=i(document).scrollTop(),d="static";if(r>=a.sidebar.offset().top+(a.paddingTop-a.options.additionalMarginTop)){var c,p=a.paddingTop+t.additionalMarginTop,b=a.paddingBottom+a.marginBottom+t.additionalMarginBottom,l=a.sidebar.offset().top,f=a.sidebar.offset().top+o(a.container),h=0+t.additionalMarginTop,g=a.stickySidebar.outerHeight()+p+b<i(window).height();c=g?h+a.stickySidebar.outerHeight():i(window).height()-a.marginBottom-a.paddingBottom-t.additionalMarginBottom;var u=l-r+a.paddingTop,S=f-r-a.paddingBottom-a.marginBottom,y=a.stickySidebar.offset().top-r,m=a.previousScrollTop-r;"fixed"==a.stickySidebar.css("position")&&"modern"==a.options.sidebarBehavior&&(y+=m),"stick-to-top"==a.options.sidebarBehavior&&(y=t.additionalMarginTop),"stick-to-bottom"==a.options.sidebarBehavior&&(y=c-a.stickySidebar.outerHeight()),y=m>0?Math.min(y,h):Math.max(y,c-a.stickySidebar.outerHeight()),y=Math.max(y,u),y=Math.min(y,S-a.stickySidebar.outerHeight());var k=a.container.height()==a.stickySidebar.outerHeight();d=(k||y!=h)&&(k||y!=c-a.stickySidebar.outerHeight())?r+y-a.sidebar.offset().top-a.paddingTop<=t.additionalMarginTop?"static":"absolute":"fixed"}if("fixed"==d){var v=i(document).scrollLeft();a.stickySidebar.css({position:"fixed",width:n(a.stickySidebar)+"px",transform:"translateY("+y+"px)",left:a.sidebar.offset().left+parseInt(a.sidebar.css("padding-left"))-v+"px",top:"0px"})}else if("absolute"==d){var x={};"absolute"!=a.stickySidebar.css("position")&&(x.position="absolute",x.transform="translateY("+(r+y-a.sidebar.offset().top-a.stickySidebarPaddingTop-a.stickySidebarPaddingBottom)+"px)",x.top="0px"),x.width=n(a.stickySidebar)+"px",x.left="",a.stickySidebar.css(x)}else"static"==d&&e();"static"!=d&&1==a.options.updateSidebarHeight&&a.sidebar.css({"min-height":a.stickySidebar.outerHeight()+a.stickySidebar.offset().top-a.sidebar.offset().top+a.paddingBottom}),a.previousScrollTop=r}},a.onScroll(a),i(document).on("scroll."+a.options.namespace,function(i){return function(){i.onScroll(i)}}(a)),i(window).on("resize."+a.options.namespace,function(i){return function(){i.stickySidebar.css({position:"static"}),i.onScroll(i)}}(a)),"undefined"!=typeof ResizeSensor&&new ResizeSensor(a.stickySidebar[0],function(i){return function(){i.onScroll(i)}}(a))})}function n(i){var t;try{t=i[0].getBoundingClientRect().width}catch(i){}return"undefined"==typeof t&&(t=i.width()),t}var s={containerSelector:"",additionalMarginTop:0,additionalMarginBottom:0,updateSidebarHeight:!0,minWidth:0,disableOnResponsiveLayouts:!0,sidebarBehavior:"modern",defaultPosition:"relative",namespace:"TSS"};return t=i.extend(s,t),t.additionalMarginTop=parseInt(t.additionalMarginTop)||0,t.additionalMarginBottom=parseInt(t.additionalMarginBottom)||0,e(t,this),this}}(jQuery);(function(a){a.fn.lazyload=function(b){var c={threshold:0,failurelimit:0,event:"scroll",effect:"show",container:window};if(b){a.extend(c,b)}var d=this;if("scroll"==c.event){a(c.container).bind("scroll",function(b){var e=0;d.each(function(){if(a.abovethetop(this,c)||a.leftofbegin(this,c)){}else if(!a.belowthefold(this,c)&&!a.rightoffold(this,c)){a(this).trigger("appear")}else{if(e++>c.failurelimit){return false}}});var f=a.grep(d,function(a){return!a.loaded});d=a(f)})}this.each(function(){var b=this;if(undefined==a(b).attr("original")){a(b).attr("original",a(b).attr("src"))}if("scroll"!=c.event||undefined==a(b).attr("src")||c.placeholder==a(b).attr("src")||a.abovethetop(b,c)||a.leftofbegin(b,c)||a.belowthefold(b,c)||a.rightoffold(b,c)){if(c.placeholder){a(b).attr("src",c.placeholder)}else{a(b).removeAttr("src")}b.loaded=false}else{b.loaded=true}a(b).one("appear",function(){if(!this.loaded){a("<img />").bind("load",function(){a(b).hide().attr("src",a(b).attr("original"))[c.effect](c.effectspeed);b.loaded=true}).attr("src",a(b).attr("original"))}});if("scroll"!=c.event){a(b).bind(c.event,function(c){if(!b.loaded){a(b).trigger("appear")}})}});a(c.container).trigger(c.event);return this};a.belowthefold=function(b,c){if(c.container===undefined||c.container===window){var d=a(window).height()+a(window).scrollTop()}else{var d=a(c.container).offset().top+a(c.container).height()}return d<=a(b).offset().top-c.threshold};a.rightoffold=function(b,c){if(c.container===undefined||c.container===window){var d=a(window).width()+a(window).scrollLeft()}else{var d=a(c.container).offset().left+a(c.container).width()}return d<=a(b).offset().left-c.threshold};a.abovethetop=function(b,c){if(c.container===undefined||c.container===window){var d=a(window).scrollTop()}else{var d=a(c.container).offset().top}return d>=a(b).offset().top+c.threshold+a(b).height()};a.leftofbegin=function(b,c){if(c.container===undefined||c.container===window){var d=a(window).scrollLeft()}else{var d=a(c.container).offset().left}return d>=a(b).offset().left+c.threshold+a(b).width()};a.extend(a.expr[":"],{"below-the-fold":"$.belowthefold(a, {threshold : 0, container: window})","above-the-fold":"!$.belowthefold(a, {threshold : 0, container: window})","right-of-fold":"$.rightoffold(a, {threshold : 0, container: window})","left-of-fold":"!$.rightoffold(a, {threshold : 0, container: window})"})})(jQuery);$(function(){$("img:not(#sidebar-outer img)").lazyload({placeholder:"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg9KdHfgIca9cYdZzUWpEpKv0UzqD-dntcLJPrHUvW8skPybRjYCstyNxMe_V_d5PQhH1z21cmiObSl8QpaS6UfMZnH_44Rs5JuZs0WJr_GeLVyKmH0jZZe8AbsGjWQOlFUyYujRbjX3jmN/s1600/Loading_icon.gif",effect:"fadeIn",threshold:"-100"})});
 //]]>
</script>

II. Kiểm tra tốc độ tải Website với Tools Pingdom

Một số request phổ biến mà mình đã tối ưu:

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