Harness the Power of Accelerated Domains Prefetching For Maximum Performance

A little less than a year ago, we introduced Accelerated Domains as an add-on to any site hosted in the Servebolt Cloud. It’s been our most popular add-on to date as it does exactly what the name promises from the start. It accelerates your domain. Accelerated Domains will make your site faster, more scalable, greener, and more secure. That’s a lot of functionality right there, but that hasn’t stopped us from continuously improving its features over the last year. As promised.

Today, we’re happy to introduce a new feature for Accelerated Domains called Accelerated Domains Prefetching. This feature prefetches the assets of your site. All vastly improve your site’s performance.

Improving Your Site’s Performance

Accelerated Domains Prefetch prefetches CSS and JavaScript assets. This means those assets have been preloaded in the browser already before someone has actually clicked on a menu item link, for instance. This reduces the loading times of the relevant pages and assets to be virtually instantly loaded. Prefetching especially has a great effect on visitors to your site that have high latency to the origin server’s location.

All in all, your Accelerated Domains-powered website will load pages much faster and appear snappier. For all visitors across the globe, of course.

How it Works

The idea behind the prefetching feature is that Accelerated Domains Prefetching pre-populates the cache with content a site visitor is likely to request next. This guarantees a higher cache hit rate and, thus, a faster experience for the user. 

It does so by determining/reading the assets of a webpage, such as CSS and JavaScript files. It then writes the location of those assets in manifest files. The content of the manifest files is then loaded into the cache node closest to the visitor, which results in a reduction of the load time of your stylesheets and your script files. This is made possible by loading them in parallel in the background. 

Accelerated Domains Prefetch covers both CSS files and JavaScript files from plugins and themes. This means that when you navigate to any page of the site, the assets have already been preloaded–and, as such ready to be served in no time!

Accelerated Domains Prefetching cleverly listens in during the loading of your front page in WordPress. Based on what it finds, it determines which assets should be preloaded. This is what the contents of the manifest-style.txt would look like if your site has the Twenty Twenty One theme activated, for instance:


If you’re not yet using Accelerated Domains for your site, now’s the time to upgrade your site to its fastest, greenest, most secure, and most scale version. Order or learn more in detail about what Accelerated Domains can do for your site.

Servebolt Optimizer for WordPress 3.5 Update

Update our Servebolt Optimizer for WordPress plugin to version 3.5 to integrate Accelerated Domains Prefetching to work. Version 3.5, which will be released today, also includes the following updates:

Automatic WordPress Cron setup

WordPress has a built-in cron system that takes care of various scheduled background tasks. It, for instance, checks periodically if there are updates available. Another feature is that it also publishes posts that have been set with a future date at the time specified. Site visitors trigger WordPress’ cron, and as such, every single visit wastes resources. This affects the performance of your WordPress site, but it also is a limiting factor in scaling your site. Using up resources that you don’t have to waste simply doesn’t scale when traffic increases.

This is why we’re recommending you switch off WordPress cron and switch to the server cron. Doing this manually can be a bit daunting, so we’ve added a way to switch to the server cron automatically in the plugin.

Not only are we saving resources by switching to the server cron, but the cron jobs will also be executed more reliably. Further resources are saved as we’re adding flock to the automatically set up corn, so we don’t run multiple crons at the same time.

Clear site cache upon logging in

When you’re logged into WordPress, your browser should serve you cached content and assets. We’ve included a new header tag that clears your browser’s cache when you log in. This ensures that you never look at cached content when logged into WordPress. This feature is currently only supported by Chrome, Firefox and Edge, and others.

Learn more about browser support for the clear-site-data feature.

WooCommerce Related Improvements

Version 3.5 improves how several things are handled in WooCommerce. Specifically the following scenarios:

  1. We’ve simplified the cache purge for a single product whenever a customer checks out in WooCommerce. We will now only be purging the product URL and not not the front page URL or any other related URLs.
  2. We now purge cache for a WooCommerce product immediately when a customer check-outs regardless of whether they have the queue-based cache purge active or not. The main reason for this change is that stock levels are generally cached and could become out of stock after the last item has been purchased.

We’ve added the option to turn off WooCommerce’s Action Scheduler queue runner. The implementation is based on code provided by WooCommerce itself and saves wasting valuable resources. We also do our best to make sure they don’t run at the same time. Turning it off will disable the default runner and set up the runner using a cron (with flock) instead. This way, we make sure both crons don’t run at the same time and make them independent of each other. You can find the setting for this in the Advanced tab inside the Performance menu of the plugin.


Check out the full changelog for more details on what version 3.5 of Servebolt Optimizer for WordPress offers.

Accelerate Your Site to the Next Level Now

If you want to get your domain truly accelerated, get in touch with us, and we’ll get it set up. The only requirement is that your site needs to be hosted in the Servebolt Cloud.

My awesome colleagues are also ready to answer any questions you might have about Accelerated Domains, so please do not hesitate to get in touch.