[
https://issues.apache.org/jira/browse/HBASE-15073?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15103546#comment-15103546
]
Ted Yu commented on HBASE-15073:
--------------------------------
bq. certain use case(s)
One use case is for time series data where FIFO compaction policy is enforced.
There would be regions whose data expires gradually and gets cleaned by the
compaction policy, leaving empty regions behind.
Region normalizer would issue region merge requests for the empty regions so
that the number of regions for the table is under control.
In the above scenario, region split request during normalization doesn't play
as important a role as that for region merge. Therefore user has the choice of
turning off region split (during normalization).
w.r.t. DESIRED_NORMALIZATION_TYPES, I don't see it in
hbase-client/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java
(master branch, branch-1 or branch-1.2)
It has been dropped since it is not referenced.
bq. Users are going to see 'MS', 'M', and 'S' and are supposed to get split,
merge, etc. from this?
Yes.
I am open to suggestion on better encoding for these two operations.
> Finer grained control over normalization actions for RegionNormalizer
> ---------------------------------------------------------------------
>
> Key: HBASE-15073
> URL: https://issues.apache.org/jira/browse/HBASE-15073
> Project: HBase
> Issue Type: Task
> Components: regionserver
> Reporter: Ted Yu
> Assignee: Ted Yu
> Fix For: 2.0.0, 1.2.0, 1.3.0
>
> Attachments: 15073-v1.txt, 15073-v2.txt, 15073-v2.txt, 15073-v3.txt,
> 15073-v4.txt, 15073-v5.txt
>
>
> Currently both region split and merge actions are carried out during
> normalization for underlying table.
> However, for certain use case(s), it would be desirable to perform only one
> type of action.
> There is one boolean flag, keyed by NORMALIZATION_ENABLED_KEY, per table that
> enables normalization.
> To provide finer grained control, we have several options:
> 1. introduce another per table flag to indicate which type(s) of actions are
> allowed ("N" for disabled, "S" for split only, "M" for merge only and "MS"
> for both split and merge)
> 2. introduce another global flag to indicate which type(s) of actions are
> allowed
> 3. modify the meaning of existing flag keyed by NORMALIZATION_ENABLED_KEY so
> that it indicates type(s) of actions
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
