The busiest online shopping season is about to start and it’s time to make a quick check on whether the top shopping sites are prepared for the big consumer rush or whether they are likely going to fail because their pages are not adhering to Web performance best practices. We analyzed the top problems and explained them in detail. Here is a glimpse:

Problem #1: Too many Redirects result in delayed First Impression

The browser can’t render any content until there is content to render. From entering the initial URL until the browser can render content there are several things that happen: Resolving DNS, establishing connections, following every HTTP redirect, downloading HTML content. One thing that can be seen on some of the retail sites is the excessive use of HTTP Redirects. Here is an example. From entering the initial URL until retrieved from the initial HTML document the browser had to follow 4 redirects taking 1.3seconds

Problem #4: 3rd Party Plugins such as Superfish

One plugin that we found several times was Superfish. We actually already blogged about this two years ago that this can lead to severe client side performance problems. Check out the blog from back then: Performance Analysis of dynamic JavaScript menus. One example this year is the following Superfish call that takes 400ms to build the dynamic menu

Read the full article including all 8 Web Performance Problems.