[
https://issues.apache.org/jira/browse/HDFS-862?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Allen Wittenauer resolved HDFS-862.
-----------------------------------
Resolution: Won't Fix
> Potential NN deadlock in processDistributedUpgradeCommand
> ---------------------------------------------------------
>
> Key: HDFS-862
> URL: https://issues.apache.org/jira/browse/HDFS-862
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: namenode
> Affects Versions: 0.22.0, 0.23.1
> Reporter: Todd Lipcon
> Attachments: cycle.png,
> org.apache.hadoop.hdfs.server.common.TestDistributedUpgrade-output.txt
>
>
> Haven't seen this in practice, but the lock order is inconsistent.
> processReport locks FSNamesystem, then calls UpgradeManager.startUpgrade,
> getUpgradeState, and getUpgradeStatus (each of which locks the
> UpgradeManager). FSNameSystem.processDistributedUpgradeCommand calls
> upgradeManager.processUpgradeCommand which is synchronized on UpgradeManager,
> which can call FSNameSystem.leaveSafeMode which synchronizes on FSNamesystem.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
