WordPress’ performance team has released a new feature plugin called Performance Lab that includes a set of performance-related improvements for core. The team, which formed just five months ago, is led by Yoast and Google-sponsored core contributors, and has had more than 250 people join its Slack channel, with many participating regularly in weekly chats.
This first release includes the following modules, which are in varying states of development:
- WebP Uploads: Creates WebP versions for new JPEG image uploads if supported by the server
- WebP Support: Adds a WebP support check in Site Health status
- Persistent Object Cache Health Check: Adds a persistent object cache check for sites with non-trivial amounts of data in Site Health status
- Audit Enqueued Assets (experimental): Adds a CSS and JS resource check in Site Health status
The purpose of the plugin is to make it easy for users to test improvements in progress. Each of these modules can be enabled or disabled under a new Settings > Performance menu in the admin.
The WebP upload module can be tested by uploading JPEG images and then checking to see that the WebP versions are generated in the Media Library and displayed on the frontend. The other performance modules are checks that will show up on the Site Health status screen:
WordPress Core Committer Felix Arntz emphasized that the plugin should be considered a beta testing plugin, not a quick fix for making your WordPress site faster.
“The plugin is not going to be a suite of all crucial performance features you need to make your site fast – that’s where the existing performance plugins have their market, and the Performance Lab plugin should indeed not falsely raise an impression of wanting to compete with them,” Arntz commented in a GitHub ticket regarding the plugin’s branding.
Users should be aware they may have unexpected results when testing the plugin, especially when enabling the more experimental features that are not turned on by default. It should not be considered a replacement for other more established performance plugins. Performance Lab may also change over time, as new features are proposed for core.
“Because the Performance Lab plugin is a collection of potential WordPress core feature modules, the list of modules included may drastically change over time,” Arntz said. “New modules may be added regularly, while other modules may be removed in a future plugin version once they have landed in a WordPress core release.”
The goal for the feature plugin is to get performance improvements in progress tested more widely, weeding out edge cases before shipping the modules in a core release. Testers can log issues as GitHub issues or as wordpress.org support forum requests.