Memcached

Usage: Widely used by large-scale applications like Facebook to improve performance.

Feature: A high-performance, distributed memory object caching system that stores data in in-memory for rapid retrieval.

Management: Supports simple key-value data structures and automatically handles data expiration using an eviction policy. It is not persistent, so cached data is lost on restart.

Redis

Usage: Popular in real-time applications like Twitter for caching, session management, and more.

Feature: An in-memory data structure store that supports various data types like strings, lists, sets, and hashes, offering more flexibility compared to Memcached.

Management: Supports automatic data expiration and eviction, but also offers persistence options (e.g., snapshotting and AOF) to save data to disk, ensuring data durability in case of failure.

  • Snapshotting - refers to saving data to a binary file every x minutes, or every x write operations. Can still result in data loss in-between snapshots being recorded.
  • Append Only File (AOF) - Every write operation is logged in real-time. Allows to reconstruct the dataset in case of a crash.