they mentioned in the introduction only. "we decided to give up external caches like Redis, Memcached or Couchbase mainly because of additional time needed on

they mentioned in the introduction only. "we decided to give up external caches like Redis, Memcached or Couchbase mainly because of additional time needed on the network" reason: additional time needed on the network. there are many scenarios in which you will want to consider in-mem cache of the application, one scenario is very low latency requirements.