Google today announced that its latest PageSpeed modules help render pages up to 2x faster, particularly on mobile devices

As a major aspect of its mission to accelerate the Web, Google today announced the latest version of its mod_pagespeed (Apache) and ngx_pagespeed (NGINX) modules include new enhancements that improve performance. Google says it is seeing pages rendering up to 2x faster, especially on mobile devices.

This speedup comes thanks to two new PageSpeed optimizations (the first two) and existing PageSpeed optimizations (the last two:

• prioritize_critical_css finds the CSS rules that are used to initially render your page.
• The critical image beacon identifies the images that appear on screen when your page is first rendered and uses this to guide lazyload_images and inline_preview_images.
• defer_javascript prevents scripts from running until the page has loaded.
• convert_jpeg_to_webp reduces the size of images that are downloaded by webp-capable browsers.

This webpagetest video shows the results:

more informations you can find here »

How does PageSpeed speed up web-sites?

PageSpeed improves web page latency and bandwidth usage by changing the resources on that web page to implement web performance best practices. Each optimization is implemented as a custom filter in PageSpeed, which are executed when the HTTP server serves the website assets. Some filters simply alter the HTML content, and other filters change references to CSS, JavaScript, or images to point to more optimized versions.

PageSpeed implements custom optimization strategies for each type of asset referenced by the website, to make them smaller, reduce the loading time, and extend the cache lifetime of each asset. These optimizations include combining and minifying JavaScript and CSS files, inlining small resources, and others. PageSpeed also dynamically optimizes images by removing unused meta-data from each file, resizing the images to specified dimensions, and re-encoding images to be served in the most efficient format available to the user.

PageSpeed ships with a set of core filters designed to safely optimize the content of your site without affecting the look or behavior of your site. In addition, it provides a number of more advanced filters which can be turned on by the site owner to gain higher performance improvements.

PageSpeed can be deployed and customized for individual web sites, as well as being used by large hosting providers and CDNs to help their users improve performance of their sites, lower the latency of their pages, and decrease bandwidth usage.