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https://issues.apache.org/jira/browse/HIVE-24549?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17251546#comment-17251546
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Adesh Kumar Rao commented on HIVE-24549:
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[~jfs] If you are not planning to work on it, Can I assign it to myself?
> TxnManager should not be shared across queries
> ----------------------------------------------
>
> Key: HIVE-24549
> URL: https://issues.apache.org/jira/browse/HIVE-24549
> Project: Hive
> Issue Type: Bug
> Components: HiveServer2
> Affects Versions: 4.0.0
> Reporter: John Sherman
> Priority: Major
>
> There are various sections of code that assume the DbTxnManager is not shared
> across concurrent queries in a session.
> Such as (which gets invoked during closeOperation):
>
> [https://github.com/apache/hive/blob/3f5e01cae5b65dde7edb3fbde8ebe70c1d02f6cf/ql/src/java/org/apache/hadoop/hive/ql/Driver.java#L868-L885]
> {code:java}
> // is usually called after close() to commit or rollback a query and end
> the driver life cycle.
> // do not understand why it is needed and wonder if it could be combined
> with close.
> @Override
> public void destroy() {
> driverState.lock();
> try {
> // in the cancel case where the driver state is INTERRUPTED, destroy
> will be deferred to
> // the query process
> if (driverState.isDestroyed()) {
> return;
> } else {
> driverState.descroyed();
> }
> } finally {
> driverState.unlock();
> }
> driverTxnHandler.destroy();
> }
> {code}
> The problematic part is the: driverTxnHandler.destroy() which looks like:
> {code:java}
> void destroy() {
> boolean isTxnOpen =
> driverContext != null &&
> driverContext.getTxnManager() != null &&
> driverContext.getTxnManager().isTxnOpen();
> release(!hiveLocks.isEmpty() || isTxnOpen);
> }
> {code}
> What happens is (rough sketch):
> Q1 - starts operation, acquires txn, does operation, closes txn/cleans up
> txn info, starts fetching data
> Q2 - starts operation, acquire txn
> Q1 - calls close operation which in turn calls destroy which sees the Q2s
> transaction information and cleans it up.
> Q2 - proceeds and fails in splitGeneration when it no longer can find its
> Valid*TxnIdList information.
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