Cluster expansion aims to increase concurrency, overall performance, and storage capacity — reducing data synchronization cost is not its direct goal. Understanding why requires looking at what expansion actually does and how sync mechanisms work in a gbase database environment. Why "Reducing Sync Cost" Is Not the Primary Driver Expansion targets resource bottlenecks that users can feel: more concurrent users, slower queries, or running out of disk. Sync cost is an internal, operational metric; nobody requests more nodes just because "sync seems expensive." The expansion process itself temporarily increases sync cost dramatically . Adding Data Nodes triggers a data rebalance — essentially a massive internal sync operation that moves existing data across the newly enlarged node pool, consuming significant network bandwidth and disk I/O. Sync cost depends on architecture, not just node count .…