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https://issues.apache.org/jira/browse/HBASE-17852?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16280521#comment-16280521
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Josh Elser commented on HBASE-17852:
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bq. Yea, retry would be good. File a JIRA?
HBASE-19441. Tagged in the "Phase 4" umbrella.
{quote}
So, I'd say, there are many things implicitly broken with current design.
Strong -1 on shipping it unless they are fixed.
{quote}
[~appy], while I appreciate the keen eye you're applying here, how can we move
forward here? I know it's very frustrating for Vlad to have something that he's
already built+tested be taken back to the drawing board abruptly. Do you truly
feel like this feature is harmful as compared to what the current
implementation is?
I'd prefer to see this land in master, then we take the concept back to the
drawing board and, with all of your help, we revisit this and come up with a
design and implementation that works for concurrent backup sessions (as Vlad
has this on the Phase4 roadmap already).
> Add Fault tolerance to HBASE-14417 (Support bulk loaded files in incremental
> backup)
> ------------------------------------------------------------------------------------
>
> Key: HBASE-17852
> URL: https://issues.apache.org/jira/browse/HBASE-17852
> Project: HBase
> Issue Type: Sub-task
> Reporter: Vladimir Rodionov
> Assignee: Vladimir Rodionov
> Fix For: 2.0.0
>
> Attachments: HBASE-17852-v1.patch, HBASE-17852-v2.patch,
> HBASE-17852-v3.patch, HBASE-17852-v4.patch, HBASE-17852-v5.patch,
> HBASE-17852-v6.patch, HBASE-17852-v7.patch, HBASE-17852-v8.patch,
> HBASE-17852-v9.patch
>
>
> Design approach rollback-via-snapshot implemented in this ticket:
> # Before backup create/delete/merge starts we take a snapshot of the backup
> meta-table (backup system table). This procedure is lightweight because meta
> table is small, usually should fit a single region.
> # When operation fails on a server side, we handle this failure by cleaning
> up partial data in backup destination, followed by restoring backup
> meta-table from a snapshot.
> # When operation fails on a client side (abnormal termination, for example),
> next time user will try create/merge/delete he(she) will see error message,
> that system is in inconsistent state and repair is required, he(she) will
> need to run backup repair tool.
> # To avoid multiple writers to the backup system table (backup client and
> BackupObserver's) we introduce small table ONLY to keep listing of bulk
> loaded files. All backup observers will work only with this new tables. The
> reason: in case of a failure during backup create/delete/merge/restore, when
> system performs automatic rollback, some data written by backup observers
> during failed operation may be lost. This is what we try to avoid.
> # Second table keeps only bulk load related references. We do not care about
> consistency of this table, because bulk load is idempotent operation and can
> be repeated after failure. Partially written data in second table does not
> affect on BackupHFileCleaner plugin, because this data (list of bulk loaded
> files) correspond to a files which have not been loaded yet successfully and,
> hence - are not visible to the system
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