Redis as More Than a Cache: Queues, Sessions, and Pub/Sub

Redis: A Swiss Army Knife

Redis is an in-memory data store with sub-millisecond latency. But it is far more than a key-value cache — its built-in data structures make it a versatile tool.

Queues with Redis

Laravel Horizon uses Redis lists and sorted sets for job queues. The advantages over database queues:

• Performance: Redis processes millions of jobs per second — no database locks, no polling.
• Priorities: Multiple queues with configurable worker assignments.
• Monitoring: Horizon dashboard with real-time insight into queue utilization and errors.

Sessions and Rate Limiting

• Sessions: Redis sessions are faster than database sessions and survive deployments (unlike file sessions).
• Rate Limiting: Redis INCR with TTL is the foundation for Laravel's rate limiter — atomic and fast.
• Distributed Locks: Cache::lock() uses Redis for mutex operations across multiple servers.

Pub/Sub and Streams

• Pub/Sub: Real-time messaging between services — ideal for Laravel Broadcasting with WebSockets.
• Streams: Persistent message queues with consumer groups — similar to Kafka but easier to operate.

Our Recommendation

In every Laravel project, we deploy Redis — at minimum for cache and sessions, often also for queues and broadcasting. With Redis Sentinel or Cluster, high availability is not an issue either.