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https://issues.apache.org/jira/browse/CASSANDRA-15295?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Jordan West updated CASSANDRA-15295:
------------------------------------
    Reviewers: Jordan West, Jordan West  (was: Jordan West)
               Jordan West, Jordan West
       Status: Review In Progress  (was: Patch Available)

> Running into deadlock when do CommitLog initialization
> ------------------------------------------------------
>
>                 Key: CASSANDRA-15295
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-15295
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Local/Commit Log
>            Reporter: Zephyr Guo
>            Assignee: Zephyr Guo
>            Priority: Normal
>         Attachments: jstack.log, pstack.log, screenshot-1.png, 
> screenshot-2.png, screenshot-3.png
>
>
> Recently, I found a cassandra(3.11.4) node stuck in STARTING status for a 
> long time.
>  I used jstack to saw what happened. The main thread stuck in 
> *AbstractCommitLogSegmentManager.awaitAvailableSegment*
>  !screenshot-1.png! 
> The strange thing is COMMIT-LOG-ALLOCATOR thread state was runnable but it 
> was not actually running.  
>  !screenshot-2.png! 
> And then I used pstack to troubleshoot. I found COMMIT-LOG-ALLOCATOR block on 
> java class initialization.
>   !screenshot-3.png! 
> This is a deadlock obviously. CommitLog waits for a CommitLogSegment when 
> initializing. In this moment, the CommitLog class is not initialized and the 
> main thread holds the class lock. After that, COMMIT-LOG-ALLOCATOR creates a 
> CommitLogSegment with exception and call *CommitLog.handleCommitError*(static 
> method).  COMMIT-LOG-ALLOCATOR will block on this line because CommitLog 
> class is still initializing.
>  
>  



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