[
https://issues.apache.org/jira/browse/HDFS-119?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13253022#comment-13253022
]
Suresh Srinivas commented on HDFS-119:
--------------------------------------
+1 for the patch.
> logSync() may block NameNode forever.
> -------------------------------------
>
> Key: HDFS-119
> URL: https://issues.apache.org/jira/browse/HDFS-119
> Project: Hadoop HDFS
> Issue Type: Bug
> Reporter: Konstantin Shvachko
> Assignee: Suresh Srinivas
> Fix For: 0.21.0
>
> Attachments: HDFS-119-branch-1.0.patch, HDFS-119.patch, HDFS-119.patch
>
>
> # {{FSEditLog.logSync()}} first waits until {{isSyncRunning}} is false and
> then performs syncing to file streams by calling
> {{EditLogOutputStream.flush()}}.
> If an exception is thrown after {{isSyncRunning}} is set to {{true}} all
> threads will always wait on this condition.
> An {{IOException}} may be thrown by {{EditLogOutputStream.setReadyToFlush()}}
> or a {{RuntimeException}} may be thrown by {{EditLogOutputStream.flush()}} or
> by {{processIOError()}}.
> # The loop that calls {{eStream.flush()}} for multiple
> {{EditLogOutputStream}}-s is not synchronized, which means that another
> thread may encounter an error and modify {{editStreams}} by say calling
> {{processIOError()}}. Then the iterating process in {{logSync()}} will break
> with {{IndexOutOfBoundException}}.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
