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https://issues.apache.org/jira/browse/HIVE-22420?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Aron Hamvas updated HIVE-22420:
-------------------------------
    Affects Version/s:     (was: 3.1.2)
                       3.1.0

> DbTxnManager.stopHeartbeat() should be thread-safe
> --------------------------------------------------
>
>                 Key: HIVE-22420
>                 URL: https://issues.apache.org/jira/browse/HIVE-22420
>             Project: Hive
>          Issue Type: Bug
>    Affects Versions: 3.1.0
>            Reporter: Aron Hamvas
>            Assignee: Aron Hamvas
>            Priority: Major
>
> When a transactional query is being executed and interrupted via HS2 close 
> operation request, both the background pool thread executing the query and 
> the HttpHandler thread running the close operation logic will eventually call 
> the below method:
> {noformat}
> Driver.releaseLocksAndCommitOrRollback(commit boolean)
> {noformat}
> Since this method is invoked several times in both threads, it can happen 
> that the two threads invoke it at the same time, and due to a race condition, 
> the txnId field of the DbTxnManager used by both threads could be set to 0 
> without actually successfully aborting the transaction.
> The root cause is stopHeartbeat() method in DbTxnManager not being thread 
> safe:
> When Thread-1 and Thread-2 enter stopHeartbeat() with very little time 
> difference, Thread-1 might successfully cancel the heartbeat task and set the 
> heartbeatTask field to null, while Thread-2 is trying to observe its state. 
> Thread-1 will return to the calling rollbackTxn() method and continue 
> execution there, while Thread-2 wis thrown back to the same method with a 
> NullPointerException. Thread-2 will then set txnId to 0, and Thread-1 is 
> sending this 0 value to HMS. So, the txn will not be aborted, and the locks 
> cannot be released later on either.



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