[HBASE-25649] Complete the work on moving all the balancer related classes to hbase-balancer module

• Type: Umbrella
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha-1
• Component/s: Balancer
• Hadoop Flags: Reviewed

Release Note

Introduced a ClusterInfoProvider as a bridge for LoadBalancer implementation to get cluster information and operate on the cluster, so the LoadBalancer implementation does not need to depend on HMaster/MasterServices directly. So then we could move most LoadBalancer related code to hbase-balancer module. MasterClusterInfoProvider is the actual implementation class for ClusterInfoProvider.

Moved most unit tests for load balancer to hbase-balancer module, unless it requires starting a mini cluster.

RSGroupBasedLoadBalancer and related code are still in hbase-server module. As we still have lots of migration and compatibility code, which makes it deeply tied togather with HMaster/MasterServices. We could try to move it again in 4.0.0, when we have purged the migration and compatibility code.

• Assignee: Duo Zhang
• Reporter: Duo Zhang
• Created: 09/Mar/21 06:21
• Updated: 11/Jun/21 02:16
• Resolved: 31/May/21 15:35

Description

This is the follow up issue of HBASE-23933, where we set up the new hbase-balancer module and moved several classes into it.

Issue Links

• is related to: HBASE-25675 Shrink size of hbase-server module
• is related to: HBASE-25953 Move rs group related balancer code to hbase-balancer module
• relates to: HBASE-25832 Performance improvements for StochasticLoadBalancer
• relates to: HBASE-25826 Revisit the synchronization of balancer implementation
• links to: Design Doc