VT’s Tech Blog

Web developers have to check out Google’s new Firefox + Firebug addon called Page Speed. This addon inspects your webpage to see how you can optimize the load time. Yahoo’s YSlow was good, but Google takes it a few steps further to even inspect your html and styles to see what can hider the render time of the page once it’s loaded.

Apart from the standard tests on if your content is gzipped, server headers are correct and enable client side caching and parallelizing downloads from differnent host names, this addon also does the following:

• Inspect your CSS files for unused styles
• Inspect your Cookie size – the bigger the cookie size, the bigger the request sent to the server everytime, since every request will send your cookies from the browser to the server
• Checks image compression ratios to see if you’re running on the optimal compression.
• Checks to see if your Javascript is minified, if not, it’ll show you how much you can save if you minify your javascripts
• Inspects the execution of Javascript on the page on load to show which Javascript files can be deferred in loading, by placing the Javascript loads at the end of the page instead of the head. This can drastically increase the page render times.
• If you load multiple Javascripts and CSS files, Page speed will give you recommendations to merge these into a single file.

Page Speed helps you improve your site’s performance based on the following categories of best practises:

• Optimizing caching — keeping your application’s data and logic off the network altogether
• Minimizing round-trip times — reducing the number of serial request-response cycleshttp://code.google.com/speed/page-speed/
• Minimizing request size — reducing upload size
• Minimizing payload size — reducing the size of responses, downloads, and cached pages
• Optimizing browser rendering — improving the browser’s layout of a page

Get Google Page Speed at: http://code.google.com/speed/page-speed/

Screenshots:

Google Page Speed Recommendations

CSS Optimization Recommendations

Javascript Minify Savings

Suggestion to Defer Javascript Loading