[
https://issues.apache.org/jira/browse/HDFS-13356?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16416338#comment-16416338
]
Bharat Viswanadham commented on HDFS-13356:
-------------------------------------------
It will affect when upgraded from 2.x to 3.x, so set the version to 2.7.5
> Balancer:Set default value of minBlockSize to 10mb
> ---------------------------------------------------
>
> Key: HDFS-13356
> URL: https://issues.apache.org/jira/browse/HDFS-13356
> Project: Hadoop HDFS
> Issue Type: Bug
> Affects Versions: 2.7.5
> Reporter: Bharat Viswanadham
> Assignee: Bharat Viswanadham
> Priority: Major
>
> It seems we can run into a problem while a rolling upgrade with this.
> The Balancer is upgraded after NameNodes, so once NN is upgraded it will
> expect {{minBlockSize}}parameter in {{getBlocks()}}. The Balancer cannot send
> it yet, so NN will use the default, which you set to 0. So NN will start
> unexpectedly sending small blocks to the Balancer. So we should
> # either change the default in protobuf to 10 MB
> # or treat {{minBlockSize == 0}} in {{NameNodeRpcServer}} as a signal to use
> the configuration variable
> {{DFSConfigKeys.DFS_BALANCER_GETBLOCKS_MIN_BLOCK_SIZE_KEY}}.
> If you agree, we should create a follow up jira. I wanted to backport this
> down the chain of branches, but this upgrade scenario is stopping me.
> [~barnaul] commented this in HDFS-13222 jira.
> https://issues.apache.org/jira/browse/HDFS-13222?focusedCommentId=16414855&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-16414855
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org
