1. 2021-01-22 15:58:59
    2. org.apache.flink.util.FlinkException: The assigned slot container_e01_1586576392302_14657_01_000023_2 was removed.
    3.     at org.apache.flink.runtime.resourcemanager.slotmanager.SlotManager.removeSlot(SlotManager.java:1096)
    4.     at org.apache.flink.runtime.resourcemanager.slotmanager.SlotManager.removeSlots(SlotManager.java:1066)
    5.     at org.apache.flink.runtime.resourcemanager.slotmanager.SlotManager.internalUnregisterTaskManager(SlotManager.java:1303)
    6.     at org.apache.flink.runtime.resourcemanager.slotmanager.SlotManager.unregisterTaskManager(SlotManager.java:552)
    7.     at org.apache.flink.runtime.resourcemanager.ResourceManager.closeTaskManagerConnection(ResourceManager.java:953)
    8.     at org.apache.flink.runtime.resourcemanager.ResourceManager$TaskManagerHeartbeatListener$1.run(ResourceManager.java:1310)
    9.     at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRunAsync(AkkaRpcActor.java:332)
    10.     at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRpcMessage(AkkaRpcActor.java:158)
    11.     at org.apache.flink.runtime.rpc.akka.FencedAkkaRpcActor.handleRpcMessage(FencedAkkaRpcActor.java:70)
    12.     at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.onReceive(AkkaRpcActor.java:142)
    13.     at org.apache.flink.runtime.rpc.akka.FencedAkkaRpcActor.onReceive(FencedAkkaRpcActor.java:40)
    14.     at akka.actor.UntypedActor$$anonfun$receive$1.applyOrElse(UntypedActor.scala:165)
    15.     at akka.actor.Actor$class.aroundReceive(Actor.scala:502)
    16.     at akka.actor.UntypedActor.aroundReceive(UntypedActor.scala:95)
    17.     at akka.actor.ActorCell.receiveMessage(ActorCell.scala:526)
    18.     at akka.actor.ActorCell.invoke(ActorCell.scala:495)
    19.     at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:257)
    20.     at akka.dispatch.Mailbox.run(Mailbox.scala:224)
    21.     at akka.dispatch.Mailbox.exec(Mailbox.scala:234)
    22.     at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
    23.     at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
    24.     at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
    25.     at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)

    Flink App抛出 The assigned slot container_e01_1586576392302_14657_01_000023_2 was removed.此类异常，通过查看日志，一般就是某一个Flink App内存占用大，导致TaskManager（在Yarn上就是Container）被Kill掉。如果代码写的没问题，就确实是资源不够了，其实1G Slot跑多个Task（Slot Group Share）其实挺容易出现的。因此有两种选择。可以根据具体情况，权衡选择一个。

    1. 将该Flink App调度在Per Slot内存更大的集群上。
    2. 通过slotSharingGroup("xxx")，减少Slot中共享Task的个数