Hi Robert,
    that sounds like a case of either your application state
      ultimately being bigger than the available RAM or a memory leak in
      your application (e.g., some states are not properly cleaned out
      after they are not needed anymore).
    If you have the available resources you could try and increase
      the TaskManager RAM size by a large amount and see where RAM usage
      tops out. If it ever does... in case of a memory leak it would
      grow indefinitely. Then you could reason about how to fix the
      memory leak or how to achieve your goal with a smaller application
      state.
    
    A remedy for application states larger than your available RAM is
      to use the RocksDB State backend, which allows for states larger
      than your application RAM. But that requires your kubernetes nodes
      to be equipped with a fast hard drive (SSD, optimally).
    That's how I would approach your problem...
    
    
    Hope that helps
    Jan
    
    On 27.05.21 17:51, Robert Cullen wrote:
    
    
      
      
        
          Hello Jan,
          My flink cluster is
            running on a kubernetes single node (rke). I have the JVM
            Heap Size set at 2.08 GB and the Managed Memory at 2.93 GB.
            The TaskManger reaches the max JVM Heap Size after about one
            hour then fails. Here is a snippet from the TaskManager log:
          2021-05-27 15:36:36,040 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Resolved JobManager address, beginning registration
2021-05-27 15:36:36,041 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Successful registration at job manager akka.tcp://flink@flink-jobmanager:6123/user/rpc/jobmanager_5 for job c5ff9686e944f62a24c10c6bf20a5a55.
2021-05-27 15:36:36,042 INFO  org.apache.flink.runtime.taskexecutor.TaskExecutor           [] - Establish JobManager connection for job c5ff9686e944f62a24c10c6bf20a5a55.
2021-05-27 15:36:36,042 INFO  org.apache.flink.runtime.taskexecutor.TaskExecutor           [] - Offer reserved slots to the leader of job c5ff9686e944f62a24c10c6bf20a5a55.
2021-05-27 15:36:36,042 INFO  org.apache.flink.runtime.taskexecutor.slot.TaskSlotTableImpl [] - Free slot TaskSlot(index:2, state:ALLOCATED, resource profile: ResourceProfile{cpuCores=1.0000000000000000, taskHeapMemory=500.000mb (524288000 bytes), taskOffHeapMemory=0 bytes, managedMemory=750.000mb (786432000 bytes), networkMemory=146.000mb (153092098 bytes)}, allocationId: 2f2e7abd16f21e156cab15cfa0d1d090, jobId: c5ff9686e944f62a24c10c6bf20a5a55).
2021-05-27 15:36:36,042 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Remove job c5ff9686e944f62a24c10c6bf20a5a55 from job leader monitoring.
2021-05-27 15:36:36,042 INFO  org.apache.flink.runtime.taskexecutor.TaskExecutor           [] - Close JobManager connection for job c5ff9686e944f62a24c10c6bf20a5a55.
2021-05-27 15:36:36,043 INFO  org.apache.flink.runtime.taskexecutor.TaskExecutor           [] - Receive slot request 85433366f8bf1c5efd3b88f634676764 for job c5ff9686e944f62a24c10c6bf20a5a55 from resource manager with leader id 00000000000000000000000000000000.
2021-05-27 15:36:36,043 INFO  org.apache.flink.runtime.taskexecutor.TaskExecutor           [] - Allocated slot for 85433366f8bf1c5efd3b88f634676764.
2021-05-27 15:36:36,043 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Add job c5ff9686e944f62a24c10c6bf20a5a55 for job leader monitoring.
2021-05-27 15:36:36,043 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Try to register at job manager akka.tcp://flink@flink-jobmanager:6123/user/rpc/jobmanager_5 with leader id 00000000-0000-0000-0000-000000000000.
2021-05-27 15:36:36,044 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Resolved JobManager address, beginning registration
2021-05-27 15:36:36,045 INFO  org.apache.flink.runtime.taskexecutor.DefaultJobLeaderService [] - Successful registration at job manager akka.tcp://flink@flink-jobmanager:6123/user/rpc/jobmanager_5 for job c5ff9686e944f62a24c10c6bf20a5a55.
          I guess the simple
            resolution is to increase the JVM Heap Size?
         
       
      
      
        
        
           Hi Robert,
            
              do you have some additional info? For example the last
                log message of the unreachable TaskManagers. Is the Job
                running in kubernetes? What backend are you using?
              
              From the first looks of it, I have seen this behaviour
                mostly in cases where one or more taskmanagers shut down
                due to GarbageCollection issues or OutOfMemory-Errors.
              
              
              Best regards
              Jan
              
              On 27.05.21 16:44, Robert Cullen wrote:
              
              
                
                  
                    I have a job that
                      fails after @1 hour due to a TaskManager Timeout.
                      How can I prevent this from happening?
                    2021-05-27 10:24:21
org.apache.flink.runtime.JobException: Recovery is suppressed by NoRestartBackoffTimeStrategy
    at org.apache.flink.runtime.executiongraph.failover.flip1.ExecutionFailureHandler.handleFailure(ExecutionFailureHandler.java:138)
    at org.apache.flink.runtime.executiongraph.failover.flip1.ExecutionFailureHandler.getFailureHandlingResult(ExecutionFailureHandler.java:82)
    at org.apache.flink.runtime.scheduler.DefaultScheduler.handleTaskFailure(DefaultScheduler.java:207)
    at org.apache.flink.runtime.scheduler.DefaultScheduler.maybeHandleTaskFailure(DefaultScheduler.java:197)
    at org.apache.flink.runtime.scheduler.DefaultScheduler.updateTaskExecutionStateInternal(DefaultScheduler.java:188)
    at org.apache.flink.runtime.scheduler.SchedulerBase.updateTaskExecutionState(SchedulerBase.java:677)
    at org.apache.flink.runtime.scheduler.UpdateSchedulerNgOnInternalFailuresListener.notifyTaskFailure(UpdateSchedulerNgOnInternalFailuresListener.java:51)
    at org.apache.flink.runtime.executiongraph.DefaultExecutionGraph.notifySchedulerNgAboutInternalTaskFailure(DefaultExecutionGraph.java:1462)
    at org.apache.flink.runtime.executiongraph.Execution.processFail(Execution.java:1139)
    at org.apache.flink.runtime.executiongraph.Execution.processFail(Execution.java:1079)
    at org.apache.flink.runtime.executiongraph.Execution.fail(Execution.java:783)
    at org.apache.flink.runtime.jobmaster.slotpool.SingleLogicalSlot.signalPayloadRelease(SingleLogicalSlot.java:195)
    at org.apache.flink.runtime.jobmaster.slotpool.SingleLogicalSlot.release(SingleLogicalSlot.java:182)
    at org.apache.flink.runtime.scheduler.SharedSlot.lambda$release$4(SharedSlot.java:271)
    at java.util.concurrent.CompletableFuture.uniAccept(CompletableFuture.java:670)
    at java.util.concurrent.CompletableFuture.uniAcceptStage(CompletableFuture.java:683)
    at java.util.concurrent.CompletableFuture.thenAccept(CompletableFuture.java:2010)
    at org.apache.flink.runtime.scheduler.SharedSlot.release(SharedSlot.java:271)
    at org.apache.flink.runtime.jobmaster.slotpool.AllocatedSlot.releasePayload(AllocatedSlot.java:152)
    at org.apache.flink.runtime.jobmaster.slotpool.DefaultDeclarativeSlotPool.releasePayload(DefaultDeclarativeSlotPool.java:385)
    at org.apache.flink.runtime.jobmaster.slotpool.DefaultDeclarativeSlotPool.releaseSlots(DefaultDeclarativeSlotPool.java:361)
    at org.apache.flink.runtime.jobmaster.slotpool.DeclarativeSlotPoolService.internalReleaseTaskManager(DeclarativeSlotPoolService.java:249)
    at org.apache.flink.runtime.jobmaster.slotpool.DeclarativeSlotPoolService.releaseTaskManager(DeclarativeSlotPoolService.java:230)
    at org.apache.flink.runtime.jobmaster.JobMaster.disconnectTaskManager(JobMaster.java:497)
    at org.apache.flink.runtime.jobmaster.JobMaster$TaskManagerHeartbeatListener.notifyHeartbeatTimeout(JobMaster.java:1295)
    at org.apache.flink.runtime.heartbeat.HeartbeatMonitorImpl.run(HeartbeatMonitorImpl.java:111)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRunAsync(AkkaRpcActor.java:440)
    at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRpcMessage(AkkaRpcActor.java:208)
    at org.apache.flink.runtime.rpc.akka.FencedAkkaRpcActor.handleRpcMessage(FencedAkkaRpcActor.java:77)
    at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleMessage(AkkaRpcActor.java:158)
    at akka.japi.pf.UnitCaseStatement.apply(CaseStatements.scala:26)
    at akka.japi.pf.UnitCaseStatement.apply(CaseStatements.scala:21)
    at scala.PartialFunction.applyOrElse(PartialFunction.scala:123)
    at scala.PartialFunction.applyOrElse$(PartialFunction.scala:122)
    at akka.japi.pf.UnitCaseStatement.applyOrElse(CaseStatements.scala:21)
    at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:171)
    at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:172)
    at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:172)
    at akka.actor.Actor.aroundReceive(Actor.scala:517)
    at akka.actor.Actor.aroundReceive$(Actor.scala:515)
    at akka.actor.AbstractActor.aroundReceive(AbstractActor.scala:225)
    at akka.actor.ActorCell.receiveMessage(ActorCell.scala:592)
    at akka.actor.ActorCell.invoke(ActorCell.scala:561)
    at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:258)
    at akka.dispatch.Mailbox.run(Mailbox.scala:225)
    at akka.dispatch.Mailbox.exec(Mailbox.scala:235)
    at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
    at akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
    at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
    at akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: java.util.concurrent.TimeoutException: Heartbeat of TaskManager with id 10.42.0.49:6122-e26293 timed out.
    at org.apache.flink.runtime.jobmaster.JobMaster$TaskManagerHeartbeatListener.notifyHeartbeatTimeout(JobMaster.java:1299)
    ... 27 more
                   
                  -- 
                    
                      Robert Cullen
                          240-475-4490
                        
                     
                   
                 
              
              -- 
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      -- 
      
        Robert Cullen
            240-475-4490
          
       
    
    -- 
neuland  – Büro für Informatik GmbH
Konsul-Smidt-Str. 8g, 28217 Bremen
Telefon (0421) 380107 57
Fax (0421) 380107 99
https://www.neuland-bfi.de
https://twitter.com/neuland
https://facebook.com/neulandbfi
https://xing.com/company/neulandbfi
Geschäftsführer: Thomas Gebauer, Jan Zander
Registergericht: Amtsgericht Bremen, HRB 23395 HB
USt-ID. DE 246585501