What is Redis? - Definition & Meaning
Learn what Redis is, how in-memory data storage works, and why Redis is essential for caching, sessions, and real-time applications. Discover the benefits.
Definition
Redis is an open-source, in-memory data structure store that functions as a database, cache, and message broker. By keeping data in memory, Redis achieves extremely low latency, often under one millisecond.
Technical explanation
Redis supports diverse data structures including strings, hashes, lists, sets, sorted sets, bitmaps, hyperloglogs, and streams. Its single-threaded architecture avoids lock contention and achieves hundreds of thousands of operations per second. Redis Persistence offers two mechanisms: RDB (point-in-time snapshots) and AOF (append-only file) for durability. Redis Cluster distributes data automatically across multiple nodes via hash slots (16384 total) and provides built-in failover. The pub/sub system enables real-time messaging between publishers and subscribers. Redis Streams offers a log-like data structure for event-driven architectures, comparable to Apache Kafka but simpler. Lua scripting enables atomic server-side operations. TTL (Time-To-Live) on keys automates cache invalidation. Redis Sentinel monitors master/replica topologies and performs automatic failover. With Redis 7+, features like Redis Functions and improved ACLs enhance security and programmability.
How MG Software applies this
MG Software deploys Redis as a caching layer in nearly every project to reduce database load and improve response times. We use Redis for session management in web applications, rate limiting on API endpoints, and pub/sub for real-time notifications. For client projects experiencing traffic spikes, Redis ensures the application remains responsive under heavy load.
Practical examples
- An e-commerce platform using Redis to cache product catalog queries, reducing page loads from 200ms to 5ms during peak traffic.
- A chat application leveraging Redis pub/sub to distribute messages in real-time to all connected users without polling.
- An authentication service storing session tokens in Redis with a 24-hour TTL so expired sessions are automatically cleaned up.
Related terms
Frequently asked questions
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