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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/71845/
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Review request for hive, Laszlo Bodor, prasanthj, and Slim Bouguerra.
Bugs: HIVE-22502
https://issues.apache.org/jira/browse/HIVE-22502
Repository: hive-git
Description
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A ConcurrentModificationException was thrown from the main loop of
TriggerValidatorRunnable.
The ConcurrentModificationException happened because an other thread (from
TezSessionPoolManager) updated the sessions list while the
TriggerValidatorRunnable was iterating over it.
The sessions list is updated by TezSessionPoolManager when opening or closing a
session. These operations are synchronized but the iteration in
TriggerValidatorRunnable is not.
The TriggerValidatorRunnable is executed frequently (it is scheduled at a 500ms
rate by default) therefore I was reluctant put the whole iteration into a
synchronized block. Opening and closing a session happens not so often so I
decided to make a copy of the sessions list before passing it to the
TriggerValidatorRunnable. Let me know if you think otherwise.
Diffs
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ql/src/java/org/apache/hadoop/hive/ql/exec/tez/TezSessionPoolManager.java
7c0a1fe120b
Diff: https://reviews.apache.org/r/71845/diff/1/
Testing
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qtest
Thanks,
Attila Magyar
