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https://issues.apache.org/jira/browse/HDFS-7955?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14484628#comment-14484628
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Rakesh R commented on HDFS-7955:
--------------------------------

[~zhz] attached an initial draft patch to show the changes. Following are the 
terminology I've kept in my mind while doing this.

# recover -> reconstruct
# recovery -> reconstruction
# recovering -> reconstructing

While preparing the patch, I've got doubt about backward compatibility(BC) 
flows. If we do protocol related changes, it will affect the BC, right?. It 
would be great if you could give few details about our plans to support upgrade 
path?

> Improve naming of classes, methods, and variables related to block 
> replication and recovery
> -------------------------------------------------------------------------------------------
>
>                 Key: HDFS-7955
>                 URL: https://issues.apache.org/jira/browse/HDFS-7955
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>            Reporter: Zhe Zhang
>            Assignee: Rakesh R
>         Attachments: HDFS-7955-001.patch
>
>
> Many existing names should be revised to avoid confusion when blocks can be 
> both replicated and erasure coded. This JIRA aims to solicit opinions on 
> making those names more consistent and intuitive.
> # In current HDFS _block recovery_ refers to the process of finalizing the 
> last block of a file, triggered by _lease recovery_. It is different from the 
> intuitive meaning of _recovering a lost block_. To avoid confusion, I can 
> think of 2 options:
> #* Rename this process as _block finalization_ or _block completion_. I 
> prefer this option because this is literally not a recovery.
> #* If we want to keep existing terms unchanged we can name all EC recovery 
> and re-replication logics as _reconstruction_.  
> # As Kai [suggested | 
> https://issues.apache.org/jira/browse/HDFS-7369?focusedCommentId=14361131&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14361131]
>  under HDFS-7369, several replication-based names should be made more generic:
> #* {{UnderReplicatedBlocks}} and {{neededReplications}}. E.g. we can use 
> {{LowRedundancyBlocks}}/{{AtRiskBlocks}}, and 
> {{neededRecovery}}/{{neededReconstruction}}.
> #* {{PendingReplicationBlocks}}
> #* {{ReplicationMonitor}}
> I'm sure the above list is incomplete; discussions and comments are very 
> welcome.



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