[HBASE-26712] Balancer encounters NPE in rare case

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.4.9
• Fix Version/s: 2.5.0, 3.0.0-alpha-3, 2.4.10
• Hadoop Flags: Reviewed
• Assignee: chenglei
• Reporter: Viraj Jasani
• Created: 26/Jan/22 19:34
• Updated: 01/Sep/22 10:57
• Resolved: 16/Feb/22 10:10

Description

 

ERROR [ster-1:60000.Chore.1] hbase.ScheduledChore - Caught error
java.lang.NullPointerException
    at org.apache.hadoop.hbase.master.assignment.AssignmentManager.balance(AssignmentManager.java:758)
    at org.apache.hadoop.hbase.master.HMaster.executeRegionPlansWithThrottling(HMaster.java:1834)
    at org.apache.hadoop.hbase.master.HMaster.balance(HMaster.java:1797)
    at org.apache.hadoop.hbase.master.HMaster.balance(HMaster.java:1707)
    at org.apache.hadoop.hbase.master.balancer.BalancerChore.chore(BalancerChore.java:49)
    at org.apache.hadoop.hbase.ScheduledChore.run(ScheduledChore.java:153)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
    at org.apache.hadoop.hbase.JitterScheduledThreadPoolExecutorImpl$JitteredRunnableScheduledFuture.run(JitterScheduledThreadPoolExecutorImpl.java:111)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)
 

Let's fix this.

Issue Links

• links to: GitHub Pull Request #4092
• links to: GitHub Pull Request #4112
• links to: GitHub Pull Request #4117