[jira] [Commented] (KAFKA-524) Kafka Appender causes Log4j Deadlock

["David Arthur (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/KAFKA-524?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13578104#comment-13578104 ] 

David Arthur commented on KAFKA-524:
------------------------------------

I have seen this as well. Particularly this is an issue with slf4j and the LoggerFactory deadlocking. When the appender is initializing, it creates a Producer which in turn connects to ZooKeeper. The ZooKeeper client attempts to open a logger with slf4j LoggerFactory which causes the deadlock.

One possible solution would be to defer the Producer initialization until after log4j was all setup. 
                
> Kafka Appender causes Log4j Deadlock
> ------------------------------------
>
>                 Key: KAFKA-524
>                 URL: https://issues.apache.org/jira/browse/KAFKA-524
>             Project: Kafka
>          Issue Type: Sub-task
>            Reporter: nicu marasoiu
>
> If you remove all log4j.properties from classpath (and prvent any log4j intialization previous to the one which involves kafka appender), and put KAFKA appender on rootLogger, then, even if you exclude the KAFKA appender from logger.kafka and logger.org, you get a Log4j deadlock when zookeeper send thread tries to issue a LOG.info, and for that it locks the root category (as its correct category, say org, is not yet set up in log4j, who is still in activateOptions on kafka appender).
> please read comments on the parent and ask any questions to nmarasoi@adobe.com

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira