Track 5 · Design Interview Problems
Design Redis / Memcached (Distributed Cache)
Designing an in-memory distributed cache from scratch. Consistent hashing, LRU eviction with O(1) ops, cache stampedes, and surviving node outages.
Interview problem25 min read1 interactive
On this page
- Problem framing
- Questions I ask before drawing anything
- Requirements
- Estimation
- API design
- In-memory storage engine: O(1) LRU eviction
- Evolutionary architecture: v1 MVP to v2 Distributed scale
- Cluster partitioning: Consistent Hashing with virtual nodes
- The three deadly cache failure modes
- Edge cases and failure recovery
- Cross-questions interviewers will ask
- Interview Rubric: Mid-Level vs Senior / Staff