[jira] [Resolved] (IMPALA-9611) Hang in HandoffToProbesAndWait() for multithreaded join build

["Tim Armstrong (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/IMPALA-9611?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Tim Armstrong resolved IMPALA-9611.
-----------------------------------
    Fix Version/s: Impala 4.0
       Resolution: Fixed

> Hang in HandoffToProbesAndWait() for multithreaded join build
> -------------------------------------------------------------
>
>                 Key: IMPALA-9611
>                 URL: https://issues.apache.org/jira/browse/IMPALA-9611
>             Project: IMPALA
>          Issue Type: Bug
>          Components: Backend
>    Affects Versions: Impala 3.4.0
>            Reporter: Tim Armstrong
>            Assignee: Tim Armstrong
>            Priority: Blocker
>              Labels: hang
>             Fix For: Impala 4.0
>
>
> I saw a hang triggered by test_failpoints in JoinBuilder::HandofftoProbesAndWait(), where the thread was blocked but build_side_state->is_cancelled_ is true.
> The sequence of events leading to the bug is as follows:
>  * Thread A is in HandoffToProbesAndWait(), reads is_cancelled_ and sees false.
>  * Thread B in RuntimeState::Cancel() sets is_cancelled_ = true, acquires cancellation_cvs_lock_, then calls NotifyAll() on the condition variable
>  * Thread A calls Wait() on the cv, blocks forever.
> I think this is most likely if thread A is de-scheduled at the wrong time.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org