Coordinator

1. Data Structure

Coordinator Data Structure

Coordinator mainly maintains 6 main Maps:

  • IdEpochMap: Save all Map epochs, and all instance ids (coordinator, store, schema, table)

  • CoordinatorMap:Save all Coordinators information and state

  • StoreMap: Save information and state of all Stores

  • RegionMap: The most important Map, which saves the information and status of all Regions

  • SchemaMap & TableMap: Save the information of schema and table respectively. For table, the mapping relationship of table→region is saved

2. Code Modules

Coordinator Modules

  • MetaService: Database Schema and Table related services, use server_location

  • CoordinatorService: For services related to cluster management, use server_location

  • NodeService: The service for querying node information in the cluster, using raft_location

  • RaftService: Raft data synchronization service, using raft_location

3. Start Process

Coordinator Start Process