[
https://issues.apache.org/jira/browse/HBASE-8432?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13641451#comment-13641451
]
Wang Qiang commented on HBASE-8432:
-----------------------------------
In my test case, it's less than half of the regionserver number, after several
balances(two or three), the table went balanced. But when the region number is
larger than half of the regionserver number and less than the regionserver
number, the table was still unbalanced after many times of balances. the
attachment is my patch.
> a table with unbalanced regions will balance indefinitely with the
> 'org.apache.hadoop.hbase.master.DefaultLoadBalancer'
> -----------------------------------------------------------------------------------------------------------------------
>
> Key: HBASE-8432
> URL: https://issues.apache.org/jira/browse/HBASE-8432
> Project: HBase
> Issue Type: Bug
> Components: Balancer
> Affects Versions: 0.94.5
> Environment: Linux 2.6.32-el5.x86_64
> Reporter: Wang Qiang
> Priority: Critical
> Attachments: patch_20130425_01.txt
>
>
> it happened that a table with unbalanced regions, as follows in my
> cluster(the cluster has 20 regionservers, the table has 12 regions):
> http://hadoopdev19.cm6:60030/ 1
> http://hadoopdev8.cm6:60030/ 2
> http://hadoopdev17.cm6:60030/ 1
> http://hadoopdev12.cm6:60030/ 1
> http://hadoopdev5.cm6:60030/ 1
> http://hadoopdev9.cm6:60030/ 1
> http://hadoopdev22.cm6:60030/ 1
> http://hadoopdev11.cm6:60030/ 1
> http://hadoopdev21.cm6:60030/ 1
> http://hadoopdev16.cm6:60030/ 1
> http://hadoopdev10.cm6:60030/ 1
> with the 'org.apache.hadoop.hbase.master.DefaultLoadBalancer', after 5 times
> load-balances, the table are still unbalanced:
> http://hadoopdev3.cm6:60030/ 1
> http://hadoopdev20.cm6:60030/ 1
> http://hadoopdev4.cm6:60030/ 2
> http://hadoopdev18.cm6:60030/ 1
> http://hadoopdev12.cm6:60030/ 1
> http://hadoopdev14.cm6:60030/ 1
> http://hadoopdev15.cm6:60030/ 1
> http://hadoopdev6.cm6:60030/ 1
> http://hadoopdev13.cm6:60030/ 1
> http://hadoopdev11.cm6:60030/ 1
> http://hadoopdev10.cm6:60030/ 1
> http://hadoopdev19.cm6:60030/ 1
> http://hadoopdev17.cm6:60030/ 1
> http://hadoopdev8.cm6:60030/ 1
> http://hadoopdev5.cm6:60030/ 1
> http://hadoopdev12.cm6:60030/ 1
> http://hadoopdev22.cm6:60030/ 1
> http://hadoopdev11.cm6:60030/ 1
> http://hadoopdev21.cm6:60030/ 1
> http://hadoopdev7.cm6:60030/ 2
> http://hadoopdev10.cm6:60030/ 1
> http://hadoopdev16.cm6:60030/ 1
> http://hadoopdev3.cm6:60030/ 1
> http://hadoopdev20.cm6:60030/ 1
> http://hadoopdev4.cm6:60030/ 1
> http://hadoopdev18.cm6:60030/ 2
> http://hadoopdev12.cm6:60030/ 1
> http://hadoopdev14.cm6:60030/ 1
> http://hadoopdev15.cm6:60030/ 1
> http://hadoopdev6.cm6:60030/ 1
> http://hadoopdev13.cm6:60030/ 1
> http://hadoopdev11.cm6:60030/ 1
> http://hadoopdev10.cm6:60030/ 1
> http://hadoopdev19.cm6:60030/ 1
> http://hadoopdev8.cm6:60030/ 1
> http://hadoopdev17.cm6:60030/ 1
> http://hadoopdev12.cm6:60030/ 1
> http://hadoopdev5.cm6:60030/ 1
> http://hadoopdev22.cm6:60030/ 1
> http://hadoopdev11.cm6:60030/ 1
> http://hadoopdev7.cm6:60030/ 1
> http://hadoopdev21.cm6:60030/ 2
> http://hadoopdev16.cm6:60030/ 1
> http://hadoopdev10.cm6:60030/ 1
> http://hadoopdev3.cm6:60030/ 1
> http://hadoopdev20.cm6:60030/ 1
> http://hadoopdev18.cm6:60030/ 1
> http://hadoopdev4.cm6:60030/ 1
> http://hadoopdev12.cm6:60030/ 1
> http://hadoopdev15.cm6:60030/ 1
> http://hadoopdev14.cm6:60030/ 2
> http://hadoopdev6.cm6:60030/ 1
> http://hadoopdev13.cm6:60030/ 1
> http://hadoopdev11.cm6:60030/ 1
> http://hadoopdev10.cm6:60030/ 1
> from the above logs, we can also find that some regions needn't move, but
> they moved. follow into
> 'org.apache.hadoop.hbase.master.DefaultLoadBalancer.balanceCluster()', I
> found that 'maxToTake' is error calculated.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
