How to cache queries to admin-ajax.php in WordPress to improve performance

Hello! Working with wordpress for a while now, we noticed that many actions, whether administrative in nature or building a WordPress query on the front end, are dependent on the built-in admin-ajax.php or WordPress AJAX API. Since many 3rd party plugins depend on this Ajax API to dynamically push and pull data, it is unfortunately a common occurrence to have the performance of a site impacted when many AJAX API calls are happening. One of the tell tale signs of admin-ajax.php performance issues can be seen when inspecting the network connections of rendering a particular page on your WordPress site. If you filter “admin-ajax.php” in your network tab of the developer console in your browser, you should see clearly the admin-ajax.php POST that may be taking too long. In our experience, some post grid plugins that make it easy to render a grid of posts on your page heavily rely […]