[
https://issues.apache.org/jira/browse/HDFS-15764?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17299326#comment-17299326
]
Ayush Saxena commented on HDFS-15764:
-------------------------------------
Thanx [~hadoop_yangyun] for the patch. Had a quick look.
1.
{code:java}
+ int notifyNamenodeCount = maxDirScanNotifyCount;
{code}
Seems you aren't reseting post every FBR, rather as part of every run of
DirectoryScanner? Is it, What is the frequency of this reset? I don't think
that will be high enough.
2.
{code:java}
+ if (notifyNamenodeCount-- > 0) {
+ datanode.notifyNamenodeDeletedBlock(new ExtendedBlock(bpid,
+ memBlockInfo), memBlockInfo.getStorageUuid());
+ }{code}
Here I think, instead {{notifyNamenodeCount--}}, we should just check the value
and decrement in the {{if}} block, else once the count goes below 0, still we
would be decrementing the value every time unnecessarily, similarly for the
block below
> Notify Namenode missing or new block on disk as soon as possible
> ----------------------------------------------------------------
>
> Key: HDFS-15764
> URL: https://issues.apache.org/jira/browse/HDFS-15764
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: datanode
> Reporter: Yang Yun
> Assignee: Yang Yun
> Priority: Minor
> Attachments: HDFS-15764.001.patch, HDFS-15764.002.patch,
> HDFS-15764.003.patch, HDFS-15764.004.patch
>
>
> When a bock file is deleted on disk or copied back to the disk, the
> DirectoryScanner can find the change, but the namenode know the change only
> untill the next full report. And in big cluster the period of full report is
> set to long time invterval.
> Call notifyNamenodeDeletedBlock if block files are deleted and call
> notifyNamenodeReceivedBlock if the block files is found agian. So the
> Incremental block report can send the change to namenode in next heartbeat.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
