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https://issues.apache.org/jira/browse/HBASE-18946?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16201809#comment-16201809
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ramkrishna.s.vasudevan commented on HBASE-18946:
------------------------------------------------

Checked in other branches (branch -1.x). There we have a bulk Assigner in AM. 
So all the regions to be created while doing CreateTable are collected and 
passed to the balancer along with the available servers. So we get a plan that 
is truly distributing the replicas. We don't have similar way in trunk as every 
AssignProcedure is individual and it just adds to the 'pendingAssignQueue' one 
by one.

> Stochastic load balancer assigns replica regions to the same RS
> ---------------------------------------------------------------
>
>                 Key: HBASE-18946
>                 URL: https://issues.apache.org/jira/browse/HBASE-18946
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 2.0.0-alpha-3
>            Reporter: ramkrishna.s.vasudevan
>            Assignee: ramkrishna.s.vasudevan
>             Fix For: 2.0.0-beta-1
>
>         Attachments: TestRegionReplicasWithRestartScenarios.java
>
>
> Trying out region replica and its assignment I can see that some times the 
> default LB Stocahstic load balancer assigns replica regions to the same RS. 
> This happens when we have 3 RS checked in and we have a table with 3 
> replicas. When a RS goes down then the replicas being assigned to same RS is 
> acceptable but the case when we have enough RS to assign this behaviour is 
> undesirable and does not solve the purpose of replicas. 
> [~huaxiang] and [~enis]. 



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