[
https://issues.apache.org/jira/browse/HDFS-5958?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13904904#comment-13904904
]
Alexey Kovyrin commented on HDFS-5958:
--------------------------------------
I understand perfectly well why it is happening. I've reported the issue to
make sure it will be fixed and other users wouldn't need to spend hours pulling
their hair out trying to figure out what is going on with their balance
processes hanging forever, promising to move data around and not doing it.
> One very large node in a cluster prevents balancer from balancing data
> ----------------------------------------------------------------------
>
> Key: HDFS-5958
> URL: https://issues.apache.org/jira/browse/HDFS-5958
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: balancer
> Affects Versions: 2.2.0
> Environment: Hadoop cluster with 4 nodes: 3 with 500Gb drives and one
> with 4Tb drive.
> Reporter: Alexey Kovyrin
>
> In a cluster with a set of small nodes and one much larger node balancer
> always selects the large node as the target even though it already has a copy
> of each block in the cluster.
> This causes the balancer to enter an infinite loop and stop balancing other
> nodes because each balancing iteration selects the same target and then could
> not find a single block to move.
--
This message was sent by Atlassian JIRA
(v6.1.5#6160)
