Amazon ElastiCache is a fully managed, in-memory caching service provided by AWS that supports two major caching engines: Redis and Memcached. It is designed to improve the performance of your applications by reducing the time it takes to access data from your database or other data stores by caching frequently accessed data in memory.
ElastiCache can be used to cache data and reduce the load on your databases, making applications faster and more responsive.
In-Memory Caching:
ElastiCache stores data in RAM (memory) for fast retrieval, which is significantly faster than retrieving data from disk-based storage like databases or file systems.
Supports Redis and Memcached:
Redis: A fully-featured, open-source in-memory data structure store supporting data types like strings, lists, sets, and hashes, along with advanced features like persistence, pub/sub messaging, and replication.
Memcached: A simpler, high-performance, distributed memory object caching system, which is ideal for caching and quickly accessing small data objects.
Fully Managed:
No need for hardware provisioning, software patching, or managing infrastructure. AWS handles all operational tasks such as setup, configuration, and monitoring.
Automatic failover, backups (for Redis), and scaling are managed by AWS to ensure high availability and reliability.
Scalability:
You can scale your ElastiCache clusters horizontally (adding more nodes) or vertically (choosing larger node types) depending on your needs.
Automatic partitioning (sharding) is available, especially with Redis, for distributing data across multiple nodes to improve cache size and performance.
Security:
ElastiCache supports VPC (Virtual Private Cloud) for network isolation.
It also integrates with IAM (Identity and Access Management) for controlling access to your cache clusters and supports encryption in transit and at rest for Redis.
Highly Available:
For Redis, ElastiCache supports multi-AZ replication and automatic failover to ensure high availability.
Memcached supports a simple replication mechanism for availability, though it doesn’t offer built-in high-availability features like Redis.
Event Notifications:
You can set up event notifications to monitor and receive alerts on important events, such as when nodes go down or there’s a scaling activity.
Data Persistence (for Redis):
Redis offers AOF (Append-Only File) and RDB (Redis Database Snapshot) persistence options, allowing you to save data in case of failure or restart.
