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https://issues.apache.org/jira/browse/HDFS-8058?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14482661#comment-14482661
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Jing Zhao commented on HDFS-8058:
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bq. In my thought, this would never happen, although the type is BlockInfo[],
the actual instance type is BlockInfoContiguous[] or BlockInfoStriped[], and we
also do assertBlock check before setBlock, addBlock, etc.
Yes, I understand the current patch can avoid mixed block types. But my concern
is that the way depending on the logic hidden in the code, instead of the
explicit data type, may be error prone (especially for other developers). Thus
from the API point of view, currently I still prefer declaring
{{BlockInfoContiguous[]}} and {{BlockInfoStriped[]}} separately.
> Erasure coding: use BlockInfo[] for both striped and contiguous blocks in
> INodeFile
> -----------------------------------------------------------------------------------
>
> Key: HDFS-8058
> URL: https://issues.apache.org/jira/browse/HDFS-8058
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Affects Versions: HDFS-7285
> Reporter: Yi Liu
> Assignee: Yi Liu
> Attachments: HDFS-8058.001.patch, HDFS-8058.002.patch
>
>
> This JIRA is to use {{BlockInfo[] blocks}} for both striped and contiguous
> blocks in INodeFile.
> Currently {{FileWithStripedBlocksFeature}} keeps separate list for striped
> blocks, and the methods there duplicate with those in INodeFile, and current
> code need to judge {{isStriped}} then do different things. Also if file is
> striped, the {{blocks}} in INodeFile occupy a reference memory space.
> These are not necessary, and we can use the same {{blocks}} to make code more
> clear.
> I keep {{FileWithStripedBlocksFeature}} as empty for follow use: I will file
> a new JIRA to move {{dataBlockNum}} and {{parityBlockNum}} from
> *BlockInfoStriped* to INodeFile, since ideally they are the same for all
> striped blocks in a file, and store them in block will waste NN memory.
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