hardConceptDesignMidSeniorStaff
CAP says you must choose between consistency and availability under a network partition. What are you giving up, concretely?
4 min readUpdated 2026-08-15
Answer
Short answer
Under partition you either reject requests on the side that cannot reach a quorum, or serve them and accept divergent replicas that need reconciling.CAP's C is linearisability, not ACID's C, and the choice binds only while partitioned.
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Likely follow-ups
- Where does eventual consistency put the reconciliation work, and who resolves a conflicting write?
- Why does a Raft minority partition reject writes but still risk serving a stale read?
- How do R plus W greater than RF quorums give you a consistency knob per query rather than per cluster?
- Which parts of a checkout flow can tolerate staleness, and which cannot?
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