radford nguyen has posted comments on this change. ( http://gerrit.cloudera.org:8080/13748 )
Change subject: IMPALA-8571: harden QueryEventHook execution ...................................................................... Patch Set 28: (1 comment) added some detail to the comment that needs attention http://gerrit.cloudera.org:8080/#/c/13748/28/fe/src/main/java/org/apache/impala/hooks/FixedCapacityQueryHookExecutor.java File fe/src/main/java/org/apache/impala/hooks/FixedCapacityQueryHookExecutor.java: http://gerrit.cloudera.org:8080/#/c/13748/28/fe/src/main/java/org/apache/impala/hooks/FixedCapacityQueryHookExecutor.java@313 PS28, Line 313: // TODO: IMPALA-XXX > In this latest approach, I schedule a task that will cancel the hook task i Note that this potential for unbounded growth is possible even though the hook task executor has a bounded work queue. Consider the following scenario: (1) user configures a hook timeout of 3 seconds (2) hook tasks take 1 second to execute (3) hook tasks are submitted every 2 seconds (due to query execution) Because (2) and (3), hook tasks will never fill the bounded queue and we can say that a hook task will be submitted every 2 seconds. Every hook task submitted induces a timeout task to begin after 3 seconds. Because timeout tasks are effectively submitted every 2 seconds but only run after 3 seconds, this will cause the timeout task queue to grow. -- To view, visit http://gerrit.cloudera.org:8080/13748 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: Ibb88422f7cfe86947d11ce57d2b4c63e57d1b643 Gerrit-Change-Number: 13748 Gerrit-PatchSet: 28 Gerrit-Owner: radford nguyen <radford.ngu...@gmail.com> Gerrit-Reviewer: Andrew Sherman <asher...@cloudera.com> Gerrit-Reviewer: Bharath Vissapragada <bhara...@apache.org> Gerrit-Reviewer: Fredy Wijaya <fre...@apache.org> Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Gerrit-Reviewer: radford nguyen <radford.ngu...@gmail.com> Gerrit-Comment-Date: Wed, 16 Oct 2019 14:34:55 +0000 Gerrit-HasComments: Yes
