[
https://issues.apache.org/jira/browse/HDFS-17094?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17744159#comment-17744159
]
ASF GitHub Bot commented on HDFS-17094:
---------------------------------------
zhangshuyan0 opened a new pull request, #5854:
URL: https://github.com/apache/hadoop/pull/5854
### Description of PR
When a block recovery occurs, `RecoveryTaskStriped` in datanode expects
`rBlock.getLocations()` and `rBlock. getBlockIndices()` to be in one-to-one
correspondence. However, if there are locations in stale state when NameNode
handles heartbeat, this correspondence will be disrupted. In detail, there is
no stale location in `recoveryLocations`, but the block indices array is still
complete (i.e. contains the indices of all the locations).
https://github.com/apache/hadoop/blob/c44823dadb73a3033f515329f70b2e3126fcb7be/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeManager.java#L1720-L1724
https://github.com/apache/hadoop/blob/c44823dadb73a3033f515329f70b2e3126fcb7be/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeManager.java#L1754-L1757
This will cause `BlockRecoveryWorker.RecoveryTaskStriped#recover()` to
generate a wrong internal block ID, and the corresponding datanode cannot find
the replica, thus making the recovery process fail.
https://github.com/apache/hadoop/blob/c44823dadb73a3033f515329f70b2e3126fcb7be/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockRecoveryWorker.java#L407-L416
This bug needs to be fixed.
### How was this patch tested?
Add a new unit test.
> EC: Fix bug in block recovery when there are stale datanodes
> ------------------------------------------------------------
>
> Key: HDFS-17094
> URL: https://issues.apache.org/jira/browse/HDFS-17094
> Project: Hadoop HDFS
> Issue Type: Bug
> Reporter: Shuyan Zhang
> Priority: Major
>
> When a block recovery occurs, `RecoveryTaskStriped` in datanode expects
> `rBlock.getLocations()` and `rBlock. getBlockIndices()` to be in one-to-one
> correspondence. However, if there are locations in stale state when NameNode
> handles heartbeat, this correspondence will be disrupted. In detail, there is
> no stale location in `recoveryLocations`, but the block indices array is
> still complete (i.e. contains the indices of all the locations). This will
> cause `BlockRecoveryWorker.RecoveryTaskStriped#recover` to generate a wrong
> internal block ID, and the corresponding datanode cannot find the relica,
> thus making the recovery process fail. This bug needs to be fixed.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
