[HBASE-16810] HBase Balancer throws ArrayIndexOutOfBoundsException when regionservers are in /hbase/draining znode and unloaded

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.3.0, 2.0.0
• Fix Version/s: 1.3.0, 2.0.0
• Component/s: Balancer
• Hadoop Flags: Reviewed
• Assignee: David Pope
• Reporter: Ashu Pachauri
• Created: 11/Oct/16 18:51
• Updated: 09/Nov/17 02:49
• Resolved: 13/Oct/16 17:50

Description

1. Add a regionserver znode under /hbase/draining znode.
2. Use RegionMover to unload all regions from the regionserver.
3. Run balancer.

16/09/21 14:17:33 ERROR ipc.RpcServer: Unexpected throwable object
java.lang.ArrayIndexOutOfBoundsException: 75
      at org.apache.hadoop.hbase.master.balancer.BaseLoadBalancer$Cluster.getLocalityOfRegion(BaseLoadBalancer.java:867)
      at org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer$LocalityCostFunction.cost(StochasticLoadBalancer.java:1186)
      at org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer.computeCost(StochasticLoadBalancer.java:521)
      at org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer.balanceCluster(StochasticLoadBalancer.java:309)
      at org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer.balanceCluster(StochasticLoadBalancer.java:264)
      at org.apache.hadoop.hbase.master.HMaster.balance(HMaster.java:1339)
      at org.apache.hadoop.hbase.master.MasterRpcServices.balance(MasterRpcServices.java:442)
      at org.apache.hadoop.hbase.protobuf.generated.MasterProtos$MasterService$2.callBlockingMethod(MasterProtos.java:58555)
      at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2268)
      at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:123)
      at org.apache.hadoop.hbase.ipc.RpcExecutor$Handler.run(RpcExecutor.java:188)
      at org.apache.hadoop.hbase.ipc.RpcExecutor$Handler.run(RpcExecutor.java:168)