Rapid Rebalance: Enterprise-Grade Migrations

Aerospike Enterprise v3.8.3 introduces Rapid Rebalance, a feature that significantly reduces migration times by up to 40x. This enhancement enables faster upgrade cycles and static configuration changes for operations teams while minimizing latencies during migration windows for supported applications. The high-level design of the algorithm involves streaming record metadata from the immigrator to the emigrator in digest order, using sequence numbers to ensure message order, batching metadata in chunks, and implementing a heuristic to prevent slower migrations due to metadata transfer. The implementation outlines the steps taken by both the immigrator and emigrator nodes during migration processes with Rapid Rebalance enabled. Overall, this feature greatly improves cluster rebalancing efficiency and reduces transaction latency impact during migrations.