Amazon ElastiCache
- Type
- Popular
- Launched
- 2011
An in-memory caching service delivering microsecond response times
What It Does
Amazon ElastiCache is a fully managed caching service that keeps data in memory for ultra-fast microsecond-level data access. As of October 2026, it supports three engines: Valkey, Redis OSS, and Memcached. By caching database query results and session information, it can dramatically improve overall application response times.
Use Cases
It is used for caching database query results, web application session management, real-time rankings and leaderboards, API response caching, message brokering, and geospatial data processing - anywhere high-speed data access is needed.
Everyday Analogy
Think of it like a notepad on your desk. Going to the file room (database) to retrieve documents takes time, but if you jot down frequently used information on your desk notepad (ElastiCache), you can reference it instantly. Since notepad space is limited, less frequently used information goes back to the file room.
What Is ElastiCache?
Amazon ElastiCache is a fully managed in-memory data store service from AWS. In-memory means data is kept in RAM rather than on disk, enabling dramatically faster reads and writes since disk access is eliminated. Placed as a cache layer in front of a database, it reduces database load while significantly improving application response times.
Valkey vs. Redis OSS vs. Memcached
As of October 2026, ElastiCache works with three engines: Valkey, Redis OSS, and Memcached. Valkey is an alternative to Redis, and both Valkey and Redis OSS offer rich features including data persistence, replication, sorted sets, and Pub/Sub messaging, making them useful beyond just caching. Memcached specializes in simple key-value caching with high throughput through multi-threading. When in doubt, choose Valkey, which ElastiCache names as its recommended engine.
Caching Strategies
There are two fundamental caching strategies. Lazy Loading checks the cache when data is requested and, if not found, fetches from the database and stores it in the cache. Write Through updates the cache simultaneously with database writes. Setting a TTL (time to live) to automatically remove stale cache entries is important for maintaining data freshness.
Getting Started
To get started, click 'Create cluster' in the ElastiCache console. Select an engine (Valkey, Redis OSS, or Memcached), specify the node type (performance) and number of nodes. Configure the VPC and subnets, and your cluster will be up in minutes. Connect from your application using a client library for your chosen engine.
Things to Watch Out For
- Since data is in memory, it can be lost during node failures. Use Valkey or Redis OSS replication to ensure availability
- Without proper TTL settings, stale data may continue to be served
- ElastiCache nodes are charged continuously while running, so choose smaller node types for development environments
Available Regions
Amazon ElastiCache is available in 37 Regions (as of 2026-10-09).
Asia Pacific: Hong Kong, Taipei, Tokyo, Seoul, Osaka, Mumbai, Hyderabad, Singapore, Sydney, Jakarta, Melbourne, Malaysia, New Zealand, Thailand
North America: Canada (Central), Canada West (Calgary), Mexico (Central), US East (N. Virginia), US East (Ohio), US West (N. California), US West (Oregon)
South America: São Paulo
Europe: Frankfurt, Zurich, Stockholm, Milan, Spain, Ireland, London, Paris
AWS European Sovereign Cloud: Germany
Middle East: Israel (Tel Aviv), UAE, Bahrain
Africa: Cape Town
AWS GovCloud (US): AWS GovCloud (US-East), AWS GovCloud (US-West)
References (Official AWS Resources)
The primary sources for this page are the official AWS website and documentation. Check the official pages below for the latest specifications and pricing.
If this page and the official documentation disagree, treat the official documentation as authoritative.
