Key-value store

Design a Dynamo-style store: partition keys over a consistent-hash ring, replicate each key N times and let R and W quorums trade consistency for latency and availability.

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Duration 45:00

Requirements checklist

put(key, value) and get(key) for values up to ~1 MB (typically ~1 KB).delete(key).Optional: conditional put on a version for read-modify-write.Single-digit-millisecond p99 for get and put inside a region.Writes always accepted while a quorum of replicas is reachable (high write availability).Tunable consistency per request; read-your-writes when R + W > N.Scale horizontally to tens of TB and ~1M ops/s by adding nodes, with minimal data movement.

Clarifying questions

Value size distribution and total data size?
Read/write ratio and peak throughput?
Is eventual consistency acceptable, or do some operations need read-your-writes or compare-and-set?
Single region or multi-region?

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requirements

Suggested time: about 6 minutes. Makes consistency tunable and explains which side of CAP the use case needs.

Notes for requirements