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https://issues.apache.org/jira/browse/HBASE-11667?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14088523#comment-14088523
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Hudson commented on HBASE-11667:
--------------------------------
SUCCESS: Integrated in HBase-0.98-on-Hadoop-1.1 #413 (See
[https://builds.apache.org/job/HBase-0.98-on-Hadoop-1.1/413/])
HBASE-11667 Comment ClientScanner logic for NSREs. (larsh: rev
273fe4fc81b6017ffae9ea00e8b58d65d576b84e)
* hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
> Comment ClientScanner logic for NSREs.
> --------------------------------------
>
> Key: HBASE-11667
> URL: https://issues.apache.org/jira/browse/HBASE-11667
> Project: HBase
> Issue Type: Improvement
> Reporter: Lars Hofhansl
> Assignee: Lars Hofhansl
> Priority: Minor
> Fix For: 0.99.0, 2.0.0, 0.94.23, 0.98.6
>
> Attachments: 11667-0.94.txt, 11667-doc-0.94.txt, 11667-trunk.txt,
> HBASE-11667-0.98.patch, IntegrationTestBigLinkedListWithRegionMovement.patch
>
>
> We ran into an issue with Phoenix where a RegionObserver coprocessor
> intercepts a scan and returns an aggregate (in this case a count) with a fake
> row key. It turns out this does not work when the {{ClientScanner}}
> encounters NSREs, as it uses the last key it saw to reset the scanner to try
> again (which in this case would be the fake key).
> While this is arguably a rare case and one could also argue that a region
> observer just shouldn't do this... While looking at {{ClientScanner}}'s code
> I found this logic not necessary.
> A NSRE occurred because we contacted a region server with a key that it no
> longer hosts. This is the start key, so it is always correct to retry with
> this same key. That simplifies the ClientScanner logic and also make this
> sort of coprocessors possible,
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