Overview
Memcached is a simple, blazing-fast in-memory key-value cache. It is designed to take load off databases by caching the results of expensive queries or API calls in RAM. Unlike Redis, it is intentionally minimal: opaque string/blob values, no persistence, and LRU eviction when memory fills up. It listens on port 11211 by default.
Data model and scaling
Memcached stores flat key-value pairs with a configurable memory limit. Scaling is done client-side: clients hash keys across a pool of independent servers (consistent hashing), so the cluster has no coordination overhead. There is no built-in replication or durability — treat the data as disposable.
Windows
Memcached is not distributed natively for Windows (no official build). On Windows, use WSL2 (install a Linux distribution and follow the Ubuntu procedure) or Docker (the official memcached image). This is why no native Windows page is provided here.