Quick Comparison
| Redis | Memcached | |
|---|---|---|
| Data types | Strings, lists, sets, hashes, streams | Strings only |
| Persistence | Optional (RDB, AOF) | None |
| Pub/Sub | Yes | No |
| Clustering | Redis Cluster | Client-side |
| Memory efficiency | Good | Better for simple strings |
When to Use Redis
- You need more than simple key-value caching
- Session storage, leaderboards, rate limiting
- You need pub/sub messaging
- You want data persistence
When to Use Memcached
- Simple key-value caching only
- You need maximum memory efficiency for string data
- Multi-threaded performance
Verdict
Redis for almost everything. It does everything Memcached does plus much more. Memcached only wins on raw memory efficiency for simple string caching at massive scale.