[
https://issues.apache.org/jira/browse/HDFS-7430?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14286408#comment-14286408
]
Tsz Wo Nicholas Sze commented on HDFS-7430:
-------------------------------------------
It seems that the entire BlockScanner is rewritten. This is not a code
refactoring. Is it correct?
If yes, how about making it configurable so that it is possible to use the old
scanner? The new scanner needs to take some time to be stabilized.
> Refactor the BlockScanner to use O(1) memory and use multiple threads
> ---------------------------------------------------------------------
>
> Key: HDFS-7430
> URL: https://issues.apache.org/jira/browse/HDFS-7430
> Project: Hadoop HDFS
> Issue Type: Improvement
> Affects Versions: 2.7.0
> Reporter: Colin Patrick McCabe
> Assignee: Colin Patrick McCabe
> Attachments: HDFS-7430.002.patch, HDFS-7430.003.patch,
> HDFS-7430.004.patch, HDFS-7430.005.patch, HDFS-7430.006.patch,
> HDFS-7430.007.patch, HDFS-7430.008.patch, HDFS-7430.009.patch,
> HDFS-7430.010.patch, HDFS-7430.011.patch, memory.png
>
>
> We should update the BlockScanner to use a constant amount of memory by
> keeping track of what block was scanned last, rather than by tracking the
> scan status of all blocks in memory. Also, instead of having just one
> thread, we should have a verification thread per hard disk (or other volume),
> scanning at a configurable rate of bytes per second.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
