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https://issues.apache.org/jira/browse/HBASE-16578?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15508412#comment-15508412
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Jingcheng Du commented on HBASE-16578:
--------------------------------------

This issue is for scanners on MOB cells, which includes the normal scans 
before/after compaction, even in the compaction. It means the scanners used in 
compaction have the same issue. The intermittent failures might be caused by 
this.

> Mob data loss after mob compaction and normal compcation
> --------------------------------------------------------
>
>                 Key: HBASE-16578
>                 URL: https://issues.apache.org/jira/browse/HBASE-16578
>             Project: HBase
>          Issue Type: Bug
>          Components: mob
>    Affects Versions: 2.0.0
>            Reporter: huaxiang sun
>            Assignee: Jingcheng Du
>         Attachments: TestMobCompaction.java, TestMobCompaction.java
>
>
> StoreFileScanners on MOB cells rely on the scannerOrder to find the latest 
> cells after compaction. The value of scannerOrder is assigned by the order of 
> maxSeqId of StoreFile, and this maxSeqId is valued only after the reader of 
> the StoreFile is created.
> In {{StoreFileScanner.getScannersForStoreFiles}}, the StoreFiles are sorted 
> before the readers are created and at that time the maxSeqId for each file is 
> -1 (the default value). This will lead  to a chaos in scanners on MOB cells. 
> We need to create readers just before the sorting in the method 
> {{StoreFileScanner.getScannersForStoreFiles}}.



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