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https://issues.apache.org/jira/browse/HBASE-25769?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17360329#comment-17360329
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Clara Xiong commented on HBASE-25769:
-------------------------------------

We cannot set bytable on because we are dominated by a couple of large tables. 
If we only move one table at a time, during the move, it will create 
significant impact on the balance sensitive table scans on other others too.

We have meta table which has a couple of regions/replica fewer than the node 
count, like many other users.

> Update default weight of cost functions
> ---------------------------------------
>
>                 Key: HBASE-25769
>                 URL: https://issues.apache.org/jira/browse/HBASE-25769
>             Project: HBase
>          Issue Type: Sub-task
>          Components: Balancer
>            Reporter: Clara Xiong
>            Priority: Major
>
> In production, we have seen some critical big tables that handle majority of 
> the load. Table Skew is becoming more important. With the update of table 
> skew function, balancer finally works for large table distribution on large 
> cluster. We should increase the weight from 35 to a level comparable to 
> region count skew: 500. We can even push further to replace region count skew 
> by table skew since the latter works in the same way and account for region 
> distribution per node.
> Another weight we found helpful to increase is for store file size cost 
> function. Ideally if normalizer works perfectly, we don't need to worry about 
> it since region count skew would have accounted for it. But we are often in a 
> situation it doesn't. Store file distribution needs to be given more way as 
> accommodation. we tested changing it from 5 to 200 and it works fine.



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