Topology on Raft: An Inside Look

Konstantin "Kostja" Osipov, Director Software Engineering, ScyllaDB

ScyllaDB’s drive towards strongly consistent features continues, and in this talk I will cover the upcoming implementation of safe topology changes feature: our rethinking of adding and removing nodes to a ScyllaDB cluster.

Quickly assembling a fresh cluster, performing topology and schema changes concurrently, quickly restarting a node with a different IP address or configuration – all of this has become possible thanks to a centralized – yet fault-tolerant – topology change coordinator, the new algorithm we implemented for Scylla 5.3. The next step would be automatically changing data placement to adjust to the load and distribution of data – our future plans which I will touch upon as well.