Performance team meeting summary – December, 14 2021

This is the agenda for the meeting. You can read the logs here on Slack.

Focus groups updates


If you want to have an overview of the work being done for this focus, this GitHub project is the right place to look at.

The Images focus group has had some interesting updates in the last few days. @adamsilverstein shared some of them.

First @mikeschroder is working on this issue about determining the best quality level to use when compressing images in newer formats like WebP. On this topic, @mihai2u mentionned that there could be a second approach to compress 2x+ retina images. Read the full comment here, and feel free to add your ideas as well.

Another good new for the Images focus, this module by @adamsilverstein has recently been merged into the Performance 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. When enabled, uploaded JPEG images are saved as WebP sub-sizes. Please feel free to test it and add your feedbacks in the PR comments. Complete testing instructions will follow soon.

There was also an interesting discussion about using the <source> markup to serve images in WordPress CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. and the potential plan to support the avif format. Find the entire discussion here on SlackSlack Slack is a Collaborative Group Chat Platform The WordPress community has its own Slack Channel at

Site Health

@furi3r is working on porting the work done by @audrasjb to a performance module. Follow this issue for updates about the progress.

Object caching

As for the Object caching focus, @spacedmonkey has done some work on this pull request about some enhancements to the cache APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways. component. Feel free to leave a review on the pull request of the related ticketticket Created for both bug reports and feature development on the bug tracker..


@wp-source has on schedule to create the issues for the focus group in the following days. Keep an eye on the performance plugin repository to know when these go live.

@josephscott announced that the folks at have donated to the performance team an API key that is good for 1,000 tests per month. There have been also some progress for the Blackfire and accounts for the The community site where WordPress code is created and shared by the users. This is where you can download the source code for WordPress core, plugins and themes as well as the central location for community conversations and organization. project; and we can expect start using them soon.

Here are also the log on Slack for a discussion about defining what a minimal viable performant environment looks like.

#core-media, #meeting, #performance, #performance-chat, #summary