[ 
https://issues.apache.org/jira/browse/YARN-2946?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14257354#comment-14257354
 ] 

Jian He commented on YARN-2946:
-------------------------------

Looks good, minor comment:
We can remove the exception handling in 
ZKRMStateStore#storeOrUpdateAMRMTokenSecretManagerState as it’s already handled 
in StoreOrUpdateAMRMTokenTransition.
{code}
  } catch (Exception ex) {
      LOG.info("Error storing info for AMRMTokenSecretManager", ex);
      notifyStoreOperationFailed(ex);
    }
{code}

> DeadLocks in RMStateStore<->ZKRMStateStore
> ------------------------------------------
>
>                 Key: YARN-2946
>                 URL: https://issues.apache.org/jira/browse/YARN-2946
>             Project: Hadoop YARN
>          Issue Type: Bug
>          Components: resourcemanager
>    Affects Versions: 2.7.0
>            Reporter: Rohith
>            Assignee: Rohith
>            Priority: Blocker
>         Attachments: 0001-YARN-2946.patch, 0001-YARN-2946.patch, 
> 0002-YARN-2946.patch, 0003-YARN-2946.patch, 0003-YARN-2946.patch, 
> RM_BeforeFix_Deadlock_cycle_1.png, RM_BeforeFix_Deadlock_cycle_2.png, 
> TestYARN2946.java
>
>
> Found one deadlock in ZKRMStateStore.
> # Initial stage zkClient is null because of zk disconnected event.
> # When ZKRMstatestore#runWithCheck()  wait(zkSessionTimeout) for zkClient to 
> re establish zookeeper connection either via synconnected or expired event, 
> it is highly possible that any other thred can obtain lock on 
> {{ZKRMStateStore.this}} from state machine transition events. This cause 
> Deadlock in ZKRMStateStore.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to