Memcached/MediaWiki

Activating Memcached
Memcached is an alternative to the default APCu PHP caching system, and is designed to significantly lighten the load of queries on the database. Also, the OAuth extension requires memcached.

https://www.mediawiki.org/wiki/Memcached#Setup

https://www.howtoforge.com/install-memcached-and-php5-memcached-module-on-debian-6.0-squeeze