[HBASE-26643] LoadBalancer should not return empty map

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.5.0, 2.6.0
• Fix Version/s: 2.5.0, 3.0.0-alpha-3, 2.4.10
• Component/s: proc-v2, Region Assignment, test
• Hadoop Flags: Reviewed
• Assignee: Duo Zhang
• Reporter: Duo Zhang
• Created: 03/Jan/22 15:52
• Updated: 08/Jan/22 19:38
• Resolved: 07/Jan/22 16:43

Description

After HBASE-26641, these two tests are still flaky, they also fail for me locally sometimes.

After digging, I found that, while we see this in the log output after master failover

Wanted to do round robin assignment but no servers to assign to

The UTs will fail.

Need to dig more.

Issue Links

• is broken by: HBASE-25093 the RSGroupBasedLoadBalancer#retainAssignment throws NPE
• links to: GitHub Pull Request #4005