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https://issues.apache.org/jira/browse/HDFS-10220?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15251150#comment-15251150
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Walter Su commented on HDFS-10220:
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1. isMaxFilesCheckedToReleaseLease is not requirted to be a function.
2. repeat [~vinayrpet] said, removeFilesInLease(leaseToCheck, removing); may
not be required.
3. The LOG.warn("..") is kind of verbose.
4. I think the config should keep inside. It's about implemention detail. The
re-check interval is 2s and is hard-coded too. Besides, It's too complicated
for user to pick a right value. Instead of counting the files, I prefer
counting the time. If it holds the lock for too long, log a warning and break
out for a while.
5. btw, HDFS-9311 should solve this issue.
> Namenode failover due to too long loking in LeaseManager.Monitor
> ----------------------------------------------------------------
>
> Key: HDFS-10220
> URL: https://issues.apache.org/jira/browse/HDFS-10220
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: namenode
> Reporter: Nicolas Fraison
> Assignee: Nicolas Fraison
> Priority: Minor
> Attachments: HADOOP-10220.001.patch, HADOOP-10220.002.patch,
> HADOOP-10220.003.patch, HADOOP-10220.004.patch, threaddump_zkfc.txt
>
>
> I have faced a namenode failover due to unresponsive namenode detected by the
> zkfc with lot's of WARN messages (5 millions) like this one:
> _org.apache.hadoop.hdfs.StateChange: BLOCK* internalReleaseLease: All
> existing blocks are COMPLETE, lease removed, file closed._
> On the threaddump taken by the zkfc there are lots of thread blocked due to a
> lock.
> Looking at the code, there are a lock taken by the LeaseManager.Monitor when
> some lease must be released. Due to the really big number of lease to be
> released the namenode has taken too many times to release them blocking all
> other tasks and making the zkfc thinking that the namenode was not
> available/stuck.
> The idea of this patch is to limit the number of leased released each time we
> check for lease so the lock won't be taken for a too long time period.
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