DSE In-Memory 

DataStax Enterprise includes DSE In-Memory for storing data to and accessing data exclusively from memory.

DSE In-Memory delivers in-memory computing capabilities to Cassandra. DSE In-Memory allows developers, architects, and administrators to easily choose what parts (some or all) of a database reside fully in RAM. DSE In-Memory is designed for use cases that lend themselves to in-memory computing, while allowing disk-based workloads to be serviced by Cassandra’s traditional storage model. This design allows applications with in-memory and disk-based requirements to be supported by one database platform.

DSE In-Memory delivers lightning-fast read performance for use cases that include primarily read-only workloads with slowly changing data and/or semi-static datasets. For example, a product catalog that is refreshed nightly, but read constantly during the day.

DSE In-Memory is not suitable for workloads with heavily changing data or monotonically growing datasets that can exceed the RAM capacity on the nodes/cluster.

DataStax recommends using OpsCenter to check performance metrics before and after configuring DSE In-Memory.