Lecture 9: More Replication, CRAQ

The podcast features a single speaker discussing distributed systems, focusing on ZooKeeper and CRAQ. The speaker explains ZooKeeper's API design, its use of mini-transactions, and its file system-like structure with z-nodes. Various use cases of ZooKeeper are explored, including implementing test-and-set services, configuration management, master election, and worker registration. The discussion covers the challenges of client coordination and atomicity, illustrating how to increment a counter using ZooKeeper. The speaker then transitions to CRAQ, an optimization of chain replication, highlighting its linearizability and differences from Raft, including performance considerations and failure recovery. The role of a configuration manager in maintaining chain consistency and preventing split-brain scenarios is also discussed.