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https://issues.apache.org/jira/browse/HBASE-6195?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13400033#comment-13400033
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Hudson commented on HBASE-6195:
-------------------------------

Integrated in HBase-0.94-security #37 (See 
[https://builds.apache.org/job/HBase-0.94-security/37/])
    HBASE-6195 Increment data will be lost when the memstore is flushed (Xing 
Shi) (Revision 1349627)

     Result = SUCCESS
tedyu : 
Files : 
* 
/hbase/branches/0.94/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java
* 
/hbase/branches/0.94/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java

                
> Increment data will be lost when the memstore is flushed
> --------------------------------------------------------
>
>                 Key: HBASE-6195
>                 URL: https://issues.apache.org/jira/browse/HBASE-6195
>             Project: HBase
>          Issue Type: Bug
>          Components: regionserver
>            Reporter: Xing Shi
>            Assignee: ShiXing
>             Fix For: 0.96.0, 0.94.1
>
>         Attachments: 6195-trunk-V7.patch, 6195.addendum, 
> HBASE-6195-trunk-V2.patch, HBASE-6195-trunk-V3.patch, 
> HBASE-6195-trunk-V4.patch, HBASE-6195-trunk-V5.patch, 
> HBASE-6195-trunk-V6.patch, HBASE-6195-trunk.patch
>
>
> There are two problems in increment() now:
> First:
> I see that the timestamp(the variable now) in HRegion's Increment() is 
> generated before got the rowLock, so when there are multi-thread increment 
> the same row, although it generate earlier, it may got the lock later. 
> Because increment just store one version, so till now, the result will still 
> be right.
> When the region is flushing, these increment will read the kv from snapshot 
> and memstore with whose timestamp is larger, and write it back to memstore. 
> If the snapshot's timestamp larger than the memstore, the increment will got 
> the old data and then do the increment, it's wrong.
> Secondly:
> Also there is a risk in increment. Because it writes the memstore first and 
> then HLog, so if it writes HLog failed, the client will also read the 
> incremented value.

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