Core Performance Team Update – February 28, 2023

Performance Lab

Performance Lab plugin updates are released monthly on the third Monday of the month.

February’s release 2.0.0 included bumping the minimum WordPress version to 6.1, adding an indicator to the admin bar when using SQLite, adding a file header to object-cache drop-in, fixing a PHP warning in the WebP Uploads module, and various other infrastructure improvements. 

An approach for creating standalone plugins and unbundling the Performance Lab pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the Plugin Directory or can be cost-based plugin from a third-party has been greenlit. The necessary work has already been defined (see overview issue) and engineering has commenced. 

Proposals and Discussion

Performance Team chats are held weekly on Tuesdays; check for current time.

The WordPress CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. Performance Team roadmap for 2023 was recently published along with an announcement post. Thanks to everyone who contributed to this.

The image fetchpriority attribute is now standardized, unblocking the team for working on a proposal for automatically adding the attribute to the LCP image in WordPress core, based on the existing Performance Lab module.

Work in the measurement focus continues on the infrastructure of the Plugin Checker, progress can be seen in this GitHub repo. Separately, a script for benchmarking Web Vitals of any website in the lab is also being worked on (see pull request). The team has also started focusing on a path for easier profiling WordPress performance: An initial PR has been created to add support for profiling with XHProf to the official `wp-env` WordPress package.


In addition to Performance Lab, the Performance Team also works on performance-related tickets in core and holds a monthly Bug Bash on the first Wednesday of every month; check for current time.

WordPress 6.2 contains many performance improvements, for example caching was added to the wp_get_global_settings() function in [55155], and the WordPress core blockBlock Block is the abstract term used to describe units of markup that, composed together, form the content or layout of a webpage using the WordPress editor. The idea combines concepts of what in the past may have achieved with shortcodes, custom HTML, and embed discovery into a single consistent API and user experience. theme bug with lazy-loading the LCP image was fixed in [55318]. It’s worth highlighting that WordPress core performance overall has notably improved with 6.2, both server-side and client-side (see lab data).

The automated performance testing CI workflow was proposed for WordPress core, and a pull request has also been opened. This workflow will be very valuable for monitoring core performance automatically in the long term and thus reducing the manual performance measurement workload on contributors.