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https://issues.apache.org/jira/browse/KAFKA-589?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13490899#comment-13490899
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Jason Rosenberg commented on KAFKA-589:
---------------------------------------

I was using KafkaServerStartable.startup(), but switched to 
KafkaServer.startup(), because I wanted to have a bit more control of things, 
e.g. I want to be able know if there was a problem within the container, and 
retry, etc.  In KafkaServerStartable.startup(), if there's an exception, it 
swallows the exception, and then calls shutdown(), but the caller has no idea 
if the startup was successful or not.

But I don't think that's relevant here.  I think it's counter intuitive that 
the KafkaServer.startup() would fail to startup, and throw an exception, and 
then not cleanup after itself, and require a call to shutdown in the first 
place.
                
> Clean shutdown after startup connection failure
> -----------------------------------------------
>
>                 Key: KAFKA-589
>                 URL: https://issues.apache.org/jira/browse/KAFKA-589
>             Project: Kafka
>          Issue Type: Bug
>          Components: core
>    Affects Versions: 0.8, 0.7.2
>            Reporter: Jason Rosenberg
>            Assignee: Swapnil Ghike
>            Priority: Minor
>              Labels: bugs, newbie
>
> Hi,
> I'm embedding the kafka server (0.7.2) in an application container.   I've 
> noticed that if I try to start the server without zookeeper being available, 
> by default it gets a zk connection timeout after 6 seconds, and then throws 
> an Exception out of KafkaServer.startup()....E.g., I see this stack trace:
> Exception in thread "main" org.I0Itec.zkclient.exception.ZkTimeoutException: 
> Unable to connect to zookeeper server within timeout: 6000
>       at org.I0Itec.zkclient.ZkClient.connect(ZkClient.java:876)
>       at org.I0Itec.zkclient.ZkClient.<init>(ZkClient.java:98)
>       at org.I0Itec.zkclient.ZkClient.<init>(ZkClient.java:84)
>       at kafka.server.KafkaZooKeeper.startup(KafkaZooKeeper.scala:44)
>       at kafka.log.LogManager.<init>(LogManager.scala:93)
>       at kafka.server.KafkaServer.startup(KafkaServer.scala:58)
>         ....
>         ....
> So that's ok, I can catch the exception, and then shut everything down 
> gracefully, in this case.  However, when I do this, it seems there is a 
> daemon thread still around, which doesn't quit, and so the server never 
> actually exits the jvm.  Specifically, this thread seems to hang around:
> "kafka-logcleaner-0" prio=5 tid=7fd9b48b1000 nid=0x112c08000 waiting on 
> condition [112c07000]
>    java.lang.Thread.State: TIMED_WAITING (parking)
>       at sun.misc.Unsafe.park(Native Method)
>       - parking to wait for  <7f40d4be8> (a 
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
>       at 
> java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:196)
>       at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2025)
>       at java.util.concurrent.DelayQueue.take(DelayQueue.java:164)
>       at 
> java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:609)
>       at 
> java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:602)
>       at 
> java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
>       at 
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
>       at java.lang.Thread.run(Thread.java:680)
> Looking at the code in kafka.log.LogManager(), it does seem like it starts up 
> the scheduler to clean logs, before then trying to connect to zk (and in this 
> case fail):
>   /* Schedule the cleanup task to delete old logs */
>   if(scheduler != null) {
>     info("starting log cleaner every " + logCleanupIntervalMs + " ms")    
>     scheduler.scheduleWithRate(cleanupLogs, 60 * 1000, logCleanupIntervalMs)
>   }
> So this scheduler does not appear to be stopped if startup fails.  However, 
> if I catch the above RuntimeException, and then call KafkaServer.shutdown(), 
> then it will stop the scheduler, and all is good.
> However, it seems odd that if I get an exception when calling 
> KafkaServer.startup(), that I should still have to do a 
> KafkaServer.shutdown().  Rather, wouldn't it be better to have it internally 
> cleanup after itself if startup() gets an exception?  I'm not sure I can 
> reliably call shutdown() after a failed startup()....

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