Google’s mod_pagespeed is an open source Apache module that automatically applies best practice performance rules to web pages and their associated objects. Mod_pagespeed has more than 40 available optimization filters, including image optimization, CSS and JavaScript concatenation, minification, caching, sharding, deferring JavaScript and more. While mod_pagespeed won’t solve all performance problems, it will trim the fat from unminified text files and graphics, and reduce HTTP requests. This article tests the effect of mod_pagespeed on an example site.