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https://issues.apache.org/jira/browse/HBASE-16624?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15487595#comment-15487595
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stack commented on HBASE-16624:
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I think this a good supposition but method looks too big to inline...
> MVCC DeSerialization bug in the HFileScannerImpl
> ------------------------------------------------
>
> Key: HBASE-16624
> URL: https://issues.apache.org/jira/browse/HBASE-16624
> Project: HBase
> Issue Type: Bug
> Components: HFile
> Affects Versions: 2.0.0
> Reporter: deepankar
> Assignee: deepankar
> Priority: Blocker
> Attachments: HBASE-16624.patch
>
>
> My colleague [~naggarwal] found a bug in the deserialization of mvcc from
> HFile, As a part of the optimization of deserialization of VLong, we read a
> int at once but we forgot to convert it to unsigned one.
> This would cause issues because once we cross the integer threshold in
> sequenceId and a compaction happens we would write MAX_MEMSTORE_TS in the
> trailer as 0 (because we will be reading negative values from the file that
> got flushed with sequenceId > Integer.MAX_VALUE). And once we have
> MAX_MEMSTORE_TS as 0, and there are sequenceId values present alongside with
> KeyValues the regionserver will now start failing to read the compacted file
> and thus corruption.
> Interestingly this would happen only on the tables that don't have
> DataBlockEncoding enabled and unfortunately in our case that turned out to be
> META and a another small table.
> Fix is small (~20 chars) and attached
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