Amazon ElastiCache allows you to seamlessly set up, run, and scale popular open-Source compatible in-memory data stores in the cloud. ... Amazon ElastiCache offers fully managed Redis and Memcached for your most demanding applications that require sub-millisecond response times.
Azure Cache for Redis provides an in-memory data store based on the open-source software Redis. When used as a cache, Redis improves the performance and scalability of systems that rely heavily on backend data-stores. Performance is improved by copying frequently accessed data to fast storage located close to the application. With Azure Cache for Redis, this fast storage is located in-memory instead of being loaded from disk by a database.