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https://issues.apache.org/jira/browse/HBASE-11339?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14038559#comment-14038559
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Jingcheng Du commented on HBASE-11339:
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Thanks for the comments! [~jmhsieh] and [~ndimiduk].
Does it mean the mob files are not feasible?
bq. Why not just improve/use existing column family functionality and have use
a cf for lob/mob fields? Couldn't we just do a combination of per-cf compaction
and per-cf flushes (not sure if all or some of those features are in already)
and get to good performance while avoiding write amplification penalties?
You mean directly saving the mob into HBase and using different compaction
policy for the mob cf? The compaction on the mob cf in HBase is costly, will
probably delay the flushing and block the updates. And a large mob store leads
to frequent region split. All of these impact the HBase potentially.
In the current design (introduced in the pdf), if users are concerned for the
write performance rather than the consistency and replication, how about to
disable the WAL directly? If users want to enable the WAL and don't want the
twice writing, they could write the mob in the client side ( the way like
Lars's suggestion). The scanner and sweep tool could work as well with this if
the locator(reference) column follows the specific format.
> HBase MOB
> ---------
>
> Key: HBASE-11339
> URL: https://issues.apache.org/jira/browse/HBASE-11339
> Project: HBase
> Issue Type: New Feature
> Components: regionserver, Scanners
> Reporter: Jingcheng Du
> Assignee: Jingcheng Du
> Attachments: HBase LOB Design.pdf
>
>
> It's quite useful to save the medium binary data like images, documents
> into Apache HBase. Unfortunately directly saving the binary MOB(medium
> object) to HBase leads to a worse performance since the frequent split and
> compaction.
> In this design, the MOB data are stored in an more efficient way, which
> keeps a high write/read performance and guarantees the data consistency in
> Apache HBase.
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