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https://issues.apache.org/jira/browse/HBASE-15156?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15131515#comment-15131515
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Francis Liu commented on HBASE-15156:
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Yup it's a small change from the current patch I have. If you see there's only
one branch for the shouldAssign flag and the code is insignificant. I know all
too well how fragile the AM is. This approach simplifies the state machine. For
one thing it simplifies the state handling between splits and SSH (AKA CRP),
since it removes that not so nice nuance of having to pretend that the region
server is holding the daughters during PONR, while the other metadata in
regionstates says otherwise.
> Support first assignment of split daughters to non-parent RS
> ------------------------------------------------------------
>
> Key: HBASE-15156
> URL: https://issues.apache.org/jira/browse/HBASE-15156
> Project: HBase
> Issue Type: New Feature
> Reporter: Francis Liu
> Assignee: Francis Liu
> Attachments: HBASE-15156.patch, HBASE-15156_1.patch
>
>
> On region split, the region's daughter is always opened by the same region
> server hosting the parent region. In some cases this is not ideal:
> This feature was mainly needed for favored nodes to allow for more freedom
> when selecting favored nodes for daughter regions. ie The daughter doesn't
> have to always select the regionserver hosting the split as a favored node
> which should allow for better favored node distribution.
> Though this feature is actually useful in cases where region splits occur
> much more often than the balancer is run. It also is a bit more efficient as
> the major compaction that occurs after daughter assignment does not go to
> waste (ie cancelled half-way, loss of locality due to move, etc). We actually
> run it this way in some of our clusters even without favored nodes enabled.
> Hence I am supplying a patch which is independent of favored nodes.
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