Hazelcast
In computing, Hazelcast IMDG is an open source in-memory data grid based on Java. It is also the name of the company developing the product.
Redis
Redis (; Remote Dictionary Server) is an in-memory data structure store, used as a distributed, in-memory key–value database, cache and message broker, with optional durability. Redis supports different kinds of abstract data structures, such as strings, lists, maps, sets, sorted sets, HyperLogLogs, bitmaps, streams, and spatial indices.