curator-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Michael Morello (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CURATOR-45) LeaderSelector threw exception, but still created ephemeral node, breaking everything
Date Fri, 02 Aug 2013 13:27:49 GMT

    [ https://issues.apache.org/jira/browse/CURATOR-45?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13727674#comment-13727674
] 

Michael Morello commented on CURATOR-45:
----------------------------------------

I can reproduce the issue in a unit test, i'm working on a fix.
Basically If the retry policy expires before the session and in the mean time the connection
is back then the ephemeral node is never deleted.
The tricky part is that we don't know the name of the znode that has been created so i think
we have to use the UUID created by the withProtection(), keep it in memory and when the connection
is back do the clean up.
                
> LeaderSelector threw exception, but still created ephemeral node, breaking everything
> -------------------------------------------------------------------------------------
>
>                 Key: CURATOR-45
>                 URL: https://issues.apache.org/jira/browse/CURATOR-45
>             Project: Apache Curator
>          Issue Type: Bug
>            Reporter: Shevek
>            Assignee: Jordan Zimmerman
>
> ZooKeeper hiccupped, and then this happened:
>     2013-06-19 02:23:35,561 DEBUG [LeaderSelector-1] com.netflix.curator.RetryLoop.takeException
(RetryLoop.java:184) - Retry-able exception received
>     org.apache.zookeeper.KeeperException$ConnectionLossException: KeeperErrorCode = ConnectionLoss
for /[REMOVED]/election/_c_1ccdb2b9-7f9a-4570-9555-201c91ec2dcb-lock-
>             at org.apache.zookeeper.KeeperException.create(KeeperException.java:99) ~[zookeeper-3.5.0.jar:3.5.0--1]
>             at org.apache.zookeeper.KeeperException.create(KeeperException.java:51) ~[zookeeper-3.5.0.jar:3.5.0--1]
>             at org.apache.zookeeper.ZooKeeper.create(ZooKeeper.java:876) ~[zookeeper-3.5.0.jar:3.5.0--1]
>             at com.netflix.curator.framework.imps.CreateBuilderImpl$10.call(CreateBuilderImpl.java:625)
~[curator-framework-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.imps.CreateBuilderImpl$10.call(CreateBuilderImpl.java:609)
~[curator-framework-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.RetryLoop.callWithRetry(RetryLoop.java:106) [curator-client-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.imps.CreateBuilderImpl.pathInForeground(CreateBuilderImpl.java:605)
[curator-framework-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.imps.CreateBuilderImpl.forPath(CreateBuilderImpl.java:428)
[curator-framework-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.imps.CreateBuilderImpl.forPath(CreateBuilderImpl.java:41)
[curator-framework-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.locks.LockInternals.attemptLock(LockInternals.java:218)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.locks.InterProcessMutex.internalLock(InterProcessMutex.java:218)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.locks.InterProcessMutex.acquire(InterProcessMutex.java:74)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.leader.LeaderSelector.doWork(LeaderSelector.java:314)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.leader.LeaderSelector.doWorkLoop(LeaderSelector.java:373)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.leader.LeaderSelector.access$100(LeaderSelector.java:46)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at com.netflix.curator.framework.recipes.leader.LeaderSelector$2.call(LeaderSelector.java:195)
[curator-recipes-1.3.5-SNAPSHOT.jar:?]
>             at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) [?:1.6.0_27]
>             at java.util.concurrent.FutureTask.run(FutureTask.java:166) [?:1.6.0_27]
>             at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
[?:1.6.0_27]
>             at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
[?:1.6.0_27]
>             at java.lang.Thread.run(Thread.java:679) [?:1.6.0_27]
> However, the ephemeral node got created, and this hung leader election for this path.
> I'm investigating to work out where to put an extra guaranteed-delete. I see the case
in LockInternals, which sometimes triggers to do this cleanup, but it didn't trigger in this
case.
> You must really love our bugs by now.

--
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

Mime
View raw message