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https://issues.apache.org/jira/browse/HBASE-15249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15172206#comment-15172206
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Elliott Clark commented on HBASE-15249:
---------------------------------------

This whole normalizer seems to be running off the rails. We can't add a new 
config every time there's a new use case that the normalizer doesn't behave the 
ideal way. That leads to a feature that is so complex that everyone gets it 
wrong. It seems like the normalizer is currently using incorrect logic and 
incorrect signals. Are we sure this is a feature that will ever be complete?

> Provide lower bound on number of regions in region normalizer for pre-split 
> tables
> ----------------------------------------------------------------------------------
>
>                 Key: HBASE-15249
>                 URL: https://issues.apache.org/jira/browse/HBASE-15249
>             Project: HBase
>          Issue Type: Bug
>            Reporter: Ted Yu
>            Assignee: Ted Yu
>              Labels: normalization
>         Attachments: HBASE-15249.v1.txt, HBASE-15249.v2.txt
>
>
> AMS (Ambari Metrics System) developer found the following scenario:
> Metrics table was pre-split with many regions on large cluster (1600 nodes).
> After some time, AMS stopped working because region normalizer merged the 
> regions into few big regions which were not able to serve high read / write 
> load.
> This is a big problem since the write requests flood the regions faster than 
> the splits can happen resulting in poor performance.
> We should consider setting reasonable lower bound on region count.
> If the table is pre-split, we can use initial region count as the lower bound.



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