[YARN-6171] ConcurrentModificationException on FSAppAttempt.containersToPreempt

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.0.0-alpha2
• Fix Version/s: 2.9.0, 3.0.0-alpha4
• Component/s: fairscheduler
• Target Version/s: 3.0.0-alpha4
• Hadoop Flags: Reviewed
• Assignee: Miklos Szegedi
• Reporter: Miklos Szegedi
• Created: 10/Feb/17 19:05
• Updated: 16/Feb/17 23:34
• Resolved: 16/Feb/17 23:04

Description

I have noticed an exception that closes the Application Master occasionally with Fair scheduler.

Caused by: org.apache.hadoop.ipc.RemoteException(java.util.ConcurrentModificationException): java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(HashMap.java:922)
	at java.util.HashMap$KeyIterator.next(HashMap.java:956)
	at org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler.allocate(FairScheduler.java:1005)
	at org.apache.hadoop.yarn.server.resourcemanager.ApplicationMasterService.allocate(ApplicationMasterService.java:532)
	at org.apache.hadoop.yarn.api.impl.pb.service.ApplicationMasterProtocolPBServiceImpl.allocate(ApplicationMasterProtocolPBServiceImpl.java:60)
	at org.apache.hadoop.yarn.proto.ApplicationMasterProtocol$ApplicationMasterProtocolService$2.callBlockingMethod(ApplicationMasterProtocol.java:99)
	at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:617)
	at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1073)