• Elastic Cache types - Redis and MemeCached
• Requires heavy application code changes.
• Caches are in-memory with high performance and low latency
• Helps reduce load of database for read intensive workloads
• Helps make your application stateless??
• AWS takes care of OS maintanence/ patching, optimizations, setup, configuration, monitoring, failure recovery and backups

Architecture of Elastic Cache

For read queries

1. Cache hit
2. Cache Miss → Update Cache
3. Cache Invalidation Strategy

Session data in Elastic Cache

• User session data of the user is Amazon Elastic Cache
• user hits another instance of the application, instance retrieves the data and the user is already logged in

Redis vs Memcached

Redis

• Multi AZ with auto failover