[
https://issues.apache.org/jira/browse/FLINK-13421?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Zhu Zhu updated FLINK-13421:
----------------------------
Summary: Unexpected ConcurrentModificationException when RM notifies JM
about allocation failure (was: Unexpected ConcurrentModificationException when
RM notify JM about allocation failure)
> Unexpected ConcurrentModificationException when RM notifies JM about
> allocation failure
> ---------------------------------------------------------------------------------------
>
> Key: FLINK-13421
> URL: https://issues.apache.org/jira/browse/FLINK-13421
> Project: Flink
> Issue Type: Bug
> Components: Runtime / Coordination
> Affects Versions: 1.9.0
> Reporter: Zhu Zhu
> Priority: Blocker
> Attachments: jm_concurrentmodification.log
>
>
> When a TM lost and RM identified it first, it will notify JM about it through
> JobMaster#notifyAllocationFailure.
> We observed unexpected ConcurrentModificationException in this process, stack
> as below:
>
> Caused by: java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextNode(HashMap.java:1437)
> at java.util.HashMap$ValueIterator.next(HashMap.java:1466)
> at
> org.apache.flink.runtime.jobmaster.slotpool.SlotSharingManager$MultiTaskSlot.release(SlotSharingManager.java:477)
> at
> org.apache.flink.runtime.jobmaster.slotpool.AllocatedSlot.releasePayload(AllocatedSlot.java:149)
> at
> org.apache.flink.runtime.jobmaster.slotpool.SlotPoolImpl.tryFailingAllocatedSlot(SlotPoolImpl.java:712)
> at
> org.apache.flink.runtime.jobmaster.slotpool.SlotPoolImpl.failAllocation(SlotPoolImpl.java:692)
> at
> org.apache.flink.runtime.jobmaster.JobMaster.internalFailAllocation(JobMaster.java:538)
> at
> org.apache.flink.runtime.jobmaster.JobMaster.notifyAllocationFailure(JobMaster.java:664)
> ... 26 more
>
> This can cause an allocated slot to be removed from SlotPool#allocatedSlots
> but not all of its payload tasks get failed. Tasks may hang in scheduled
> forever, not able to fail or timeout, as in the attached log.
> It is not figured out yet that how a concurrent modification can happen. We
> do not have a debug log for it and is not able to re-pro it with debug log
> enabled yet.
> However, we can let SlotSharingManager$MultiTaskSlot do not iterate on its
> children directly to avoid ConcurrentModificationException to occur in any
> case.
--
This message was sent by Atlassian JIRA
(v7.6.14#76016)
