[
https://issues.apache.org/jira/browse/HBASE-4616?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13174934#comment-13174934
]
Alex Newman commented on HBASE-4616:
------------------------------------
So on the first part about using printable chars in for the last region.
Consider the fact that ! is a valid table char as far as I know and comes
before other printable chars on the ascii table so that's out.
I am not a big fan of the table to int mapping as I think it provides for
another level of complexity and it's own synchronization issues. Also, having
to do a direct (hdfs) filesystem operation for adding or removing regions seems
like a bad idea. After all opening files in hdfs takes like 200ms. It'd
probably be better to have another table like meta/root for something like
this. If your worried about using 29 chars consider it's most likely small when
compared to the size of the hri/row key. If we really want to cut down on
space we can just the 128bits of the md5 directly, it will make it even more
difficult to read, but it will be compact.
Pros to pulling the tablename out:
Constant overhead for large tablenames
More flexibility on what can be a tablename
More deterministic overhead
Cons:
More difficult to debug
Not what we do now
Pros to md5 vs lookup table:
One less table piece of state
Easier to debug
Tables from one cluster wont clobber tables from another
Cons to the md5 approach:
More key space overhead than a lookup table(although not with the binary
approach)
> Update hregion encoded name to reduce logic and prevent region collisions in
> META
> ---------------------------------------------------------------------------------
>
> Key: HBASE-4616
> URL: https://issues.apache.org/jira/browse/HBASE-4616
> Project: HBase
> Issue Type: Umbrella
> Reporter: Alex Newman
> Assignee: Alex Newman
> Attachments: HBASE-4616-v2.patch, HBASE-4616-v3.patch,
> HBASE-4616.patch
>
>
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
