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https://issues.apache.org/jira/browse/HDFS-14498?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17152196#comment-17152196
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Xiaoqiao He commented on HDFS-14498:
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[~sodonnell] thanks for your deep dig of this issue. I try to reproduce this
case with simple unit test. The root cause seems that check all blocks of the
file. reference to `fsn.checkFileProgress(src, pendingFile, true)` of
`org.apache.hadoop.hdfs.server.namenode.FSDirWriteFileOp#completeFileInternal`.
a. client add block but not write any data.
b. no datanode report since no data write to.
c. close file request will fail because this block replicas does not reach the
minimum threshold which is 1 by default.
d. then namenode return false after process close/complete request.
IMO, if client never renew lease for while, we should remove the last block
directly and set the file length to 0 if this file include only one block or
remove the last block and reset file length. any thought?
> LeaseManager can loop forever on the file for which create has failed
> ----------------------------------------------------------------------
>
> Key: HDFS-14498
> URL: https://issues.apache.org/jira/browse/HDFS-14498
> Project: Hadoop HDFS
> Issue Type: Bug
> Affects Versions: 2.9.0
> Reporter: Sergey Shelukhin
> Priority: Major
>
> The logs from file creation are long gone due to infinite lease logging,
> however it presumably failed... the client who was trying to write this file
> is definitely long dead.
> The version includes HDFS-4882.
> We get this log pattern repeating infinitely:
> {noformat}
> 2019-05-16 14:00:16,893 INFO
> [org.apache.hadoop.hdfs.server.namenode.LeaseManager$Monitor@b27557f]
> org.apache.hadoop.hdfs.server.namenode.LeaseManager: [Lease. Holder:
> DFSClient_NONMAPREDUCE_-20898906_61, pending creates: 1] has expired hard
> limit
> 2019-05-16 14:00:16,893 INFO
> [org.apache.hadoop.hdfs.server.namenode.LeaseManager$Monitor@b27557f]
> org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Recovering [Lease.
> Holder: DFSClient_NONMAPREDUCE_-20898906_61, pending creates: 1], src=<snip>
> 2019-05-16 14:00:16,893 WARN
> [org.apache.hadoop.hdfs.server.namenode.LeaseManager$Monitor@b27557f]
> org.apache.hadoop.hdfs.StateChange: DIR* NameSystem.internalReleaseLease:
> Failed to release lease for file <snip>. Committed blocks are waiting to be
> minimally replicated. Try again later.
> 2019-05-16 14:00:16,893 WARN
> [org.apache.hadoop.hdfs.server.namenode.LeaseManager$Monitor@b27557f]
> org.apache.hadoop.hdfs.server.namenode.LeaseManager: Cannot release the path
> <snip> in the lease [Lease. Holder: DFSClient_NONMAPREDUCE_-20898906_61,
> pending creates: 1]. It will be retried.
> org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException: DIR*
> NameSystem.internalReleaseLease: Failed to release lease for file <snip>.
> Committed blocks are waiting to be minimally replicated. Try again later.
> at
> org.apache.hadoop.hdfs.server.namenode.FSNamesystem.internalReleaseLease(FSNamesystem.java:3357)
> at
> org.apache.hadoop.hdfs.server.namenode.LeaseManager.checkLeases(LeaseManager.java:573)
> at
> org.apache.hadoop.hdfs.server.namenode.LeaseManager$Monitor.run(LeaseManager.java:509)
> at java.lang.Thread.run(Thread.java:745)
> $ grep -c "Recovering.*DFSClient_NONMAPREDUCE_-20898906_61, pending creates:
> 1" hdfs_nn*
> hdfs_nn.log:1068035
> hdfs_nn.log.2019-05-16-14:1516179
> hdfs_nn.log.2019-05-16-15:1538350
> {noformat}
> Aside from an actual bug fix, it might make sense to make LeaseManager not
> log so much, in case if there are more bugs like this...
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