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https://issues.apache.org/jira/browse/HDFS-5557?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Kihwal Lee updated HDFS-5557:
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Attachment: HDFS-5557.patch
Oops. I uploaded the first version again. Reuploading the updated patch.
> Write pipeline recovery for the last packet in the block may cause rejection
> of valid replicas
> ----------------------------------------------------------------------------------------------
>
> Key: HDFS-5557
> URL: https://issues.apache.org/jira/browse/HDFS-5557
> Project: Hadoop HDFS
> Issue Type: Bug
> Affects Versions: 0.23.9, 2.3.0
> Reporter: Kihwal Lee
> Assignee: Kihwal Lee
> Priority: Critical
> Attachments: HDFS-5557.patch, HDFS-5557.patch, HDFS-5557.patch,
> HDFS-5557.patch
>
>
> When a block is reported from a data node while the block is under
> construction (i.e. not committed or completed), BlockManager calls
> BlockInfoUnderConstruction.addReplicaIfNotPresent() to update the reported
> replica state. But BlockManager is calling it with the stored block, not
> reported block. This causes the recorded replicas' gen stamp to be that of
> BlockInfoUnderConstruction itself, not the one from reported replica.
> When a pipeline recovery is done for the last packet of a block, the
> incremental block reports with the new gen stamp may come before the client
> calling updatePipeline(). If this happens, these replicas will be incorrectly
> recorded with the old gen stamp and get removed later. The result is close
> or addAdditionalBlock failure.
> If the last block is completed, but the penultimate block is not because of
> this issue, the file won't be closed. If this file is not cleared, but the
> client goes away, the lease manager will try to recover the lease/block, at
> which point it will crash. I will file a separate jira for this shortly.
> The worst case is to reject all good ones and accepting a bad one. In this
> case, the block will get completed, but the data cannot be read until the
> next full block report containing one of the valid replicas is received.
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