System design lab

Quorum reads and writes

Pick N, W and R, take replicas down, and see exactly when a read misses the latest write.

InteractiveQuorums with N replicas
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With W = 1 and R = 1, write twice and read: the worst-case read set can contain only stale replicas. Raise either quorum until R + W > N and the stale read becomes impossible. Then take replicas down and see which operations stop working.

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