Quorum compounding is a parallel execution pattern where components run concurrently, but completion requires responses from a majority rather than every participant. For N nodes, the quorum is (N/2) + 1. section 2.4
Cluster quorum
A three-node cluster needs two responses; a five-node cluster needs three. Raft, Paxos, and Viewstamped Replication use majority agreement to reach consensus while avoiding the latency of waiting for every node. section 2.4
Use quorum compounding to reason about parallel latency and completion conditions:
- Parallel execution can still encounter tail latency as fan-out increases. section 2.4
- Waiting only for a quorum can optimize latency because slower minority responses are unnecessary. section 2.4
