Description of problem: In osp18 we no longer expose memcached to compute nodes. In 16/17 compute nodes can connect to memcached in controller nodes but it's not recommend. It can cause too many connections in case compute nodes are scaled out, and it can also cause undesired latency in DCN. Objective is to cache project and user names in oslo's dictionary backend. Version-Release number of selected component (if applicable): 17.1