Redis vs Memcached — In-Memory Cache Comparison
Redis and Memcached are the two leading in-memory caches. Redis has grown to be a more general data store; Memcached remains a minimalist key-value cache.
Quick Verdict
Redis for rich data structures (hashes, lists, sorted sets, pub/sub), persistence, clustering. Memcached for the simplest possible key-value cache with multi-threading.
Side-by-Side Spec Comparison
| Spec | Redis | Memcached |
|---|---|---|
| Data Structures | Strings, hashes, lists, sets, sorted sets, streams, HyperLogLog | Strings only |
| Persistence | Yes (RDB + AOF) | No (purely in-memory) |
| Replication | Master-replica + Sentinel | Limited (Memcached-Repcached) |
| Clustering | Redis Cluster (sharding) | No native (client-side sharding) |
| Threading | Single-threaded (Redis 6 added I/O threads) | Multi-threaded |
| Max Memory Recommended | Per-node 64-128 GB | Per-node 64 GB |
| Pub/Sub | Yes | No |
Green-highlighted cells indicate the winner for that spec.
Frequently Asked Questions
Should I use Redis or Memcached for session storage?
Redis — persistence and replication mean sessions survive restarts and host failures. Memcached loses everything on restart.
Which is faster?
Roughly equivalent on simple GET/SET — both serve millions of ops/sec. Memcached has slight edge on multi-threaded raw throughput; Redis wins on feature breadth.
Our Recommendation
Redis for sessions, queues, rich data. Memcached for the simplest possible page-fragment cache.
Need help deciding?
Email sales@prodisknetwork.com with your specific requirements. Our team will match you to the right product based on your workload, budget, and existing infrastructure.