The MemCache module allows Dolibarr to increase speed by using a cache server MemCached. According to platform, speed to show each page can be increase between 20% and 40%. This module is an applicative cache, not a PHP OPCode cache so gain effect is cumulated with any other OPCode cache like APC, eAccelerator.

A reporting page, show you cache efficiency.

http://www.dolistore.com/lang-en/modules/2-MemCached.html