Amazon ElastiCache
User Guide (API Version 2015-02-02)

Parameters and Parameter Groups

Amazon ElastiCache uses parameters to control the runtime properties of your nodes and clusters. Generally, newer engine versions include additional parameters to support the newer functionality. For tables of parameters by engine and version, see Memcached Specific Parameters and Redis Specific Parameters.

As you would expect, some parameter values, such as max_cache_memory, are determined by the engine and node type. For a table of these parameter values by node type, see Memcached Node-Type Specific Parameters and Redis Node-Type Specific Parameters.