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https://issues.apache.org/jira/browse/HBASE-11646?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14087140#comment-14087140
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Jingcheng Du commented on HBASE-11646:
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[~jmhsieh] Thanks Jon for the descriptions.
for the case#1, if a threshold is set larger, do we need to save the mob data 
back to the HBase? Or just leave them in the mob files?

> Handle the MOB in compaction
> ----------------------------
>
>                 Key: HBASE-11646
>                 URL: https://issues.apache.org/jira/browse/HBASE-11646
>             Project: HBase
>          Issue Type: Sub-task
>          Components: Compaction
>            Reporter: Jingcheng Du
>            Assignee: Jingcheng Du
>
> In the updated MOB design however, admins can set CF level thresholds that 
> would force cell values > the threshold to use the MOB write path instead of 
> the traditional path.  There are two cases where mobs need to interact with 
> this threshold
> 1) How do we handle the case when the threshold size is changed?
> 2) Today, you can bulkload hfiles that contain MOBs.  These cells will work 
> as normal inside hbase.  Unfortunately the cells with MOBs in them will never 
> benefit form the MOB write path.
> The proposal here is to modify compaction in mob enabled cf's such that the 
> threshold value is honored with compactions.  This handles case #1 -- 
> elements that should be moved out of the normal hfiles get 'compacted' into 
> refs and mob hfiles, and values that should be pulled into the cf get derefed 
> and written out wholy in the compaction.  For case #2, we can maintain the 
> same behavior and compaction would move data into the mob writepath/lifecycle.



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