[
https://issues.apache.org/jira/browse/HDFS-7678?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14537493#comment-14537493
]
Jing Zhao commented on HDFS-7678:
---------------------------------
Thanks for the great work, Zhe! The 013 patch looks pretty good to me. Just
some minors:
# The semantic of the original {{StripeRange}} used by stateful read is
different from the one used by AlignedStripe. The one used by stateful read is
not about a vertical range in a single internal block, but a contiguous range
in whole the block group. Also, because it is actually only used by the
stateful read, I think it's better to simply keep it in DFSStripedInputStream,
and have a different name for {{StripedBlockUtil#StripeRange}}.
# We can divide {{divideByteRangeIntoStripes}} into several smaller functions.
# Maybe rename {{StripedBlockUtil.StripeRange#getLength}} to {{getWidth}}?
# Let's add TODO on the two places you mentioned for bypassing the codec bug.
> Erasure coding: DFSInputStream with decode functionality (pread)
> ----------------------------------------------------------------
>
> Key: HDFS-7678
> URL: https://issues.apache.org/jira/browse/HDFS-7678
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Affects Versions: HDFS-7285
> Reporter: Li Bo
> Assignee: Zhe Zhang
> Attachments: BlockGroupReader.patch, HDFS-7678-HDFS-7285.002.patch,
> HDFS-7678-HDFS-7285.003.patch, HDFS-7678-HDFS-7285.004.patch,
> HDFS-7678-HDFS-7285.005.patch, HDFS-7678-HDFS-7285.006.patch,
> HDFS-7678-HDFS-7285.007.patch, HDFS-7678-HDFS-7285.008.patch,
> HDFS-7678-HDFS-7285.009.patch, HDFS-7678-HDFS-7285.010.patch,
> HDFS-7678-HDFS-7285.012.patch, HDFS-7678-HDFS-7285.013.patch,
> HDFS-7678.000.patch, HDFS-7678.001.patch
>
>
> A block group reader will read data from BlockGroup no matter in striping
> layout or contiguous layout. The corrupt blocks can be known before
> reading(told by namenode), or just be found during reading. The block group
> reader needs to do decoding work when some blocks are found corrupt.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
