Manual:WANObjectCache.php

Details
A new MediaWiki system that is replacing some previous caching systems including database and local object cache (including PHP accelerators).

Enabling WANObjectCache in your wiki
If  is left as the default of  , the cache will default to what is set by .

Use WANObjectCache in your code
See the [https://doc.wikimedia.org/mediawiki-core/master/php/classWANObjectCache.html doxygen documentation], which contains a class overview, method use cases and examples, and parameter documentation.