[
https://issues.apache.org/jira/browse/HBASE-25761?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17364076#comment-17364076
]
Duo Zhang commented on HBASE-25761:
-----------------------------------
The difference comparing to a general root table and master local region here
is that, even we do not split meta, the root table and master local region is
there, most of the code will be executed. For example, the tiered assignment
and initialization.
In general, for me, the first meta as root solution is very like a compromise,
you need to do lots of magics in the row key and comparator, just like what I
have done in the master local region implementation, as we will also store
procedure data in the same region. But at least, the master local region will
use different families to store the data, so when reading we do not need to add
special filters...
And about the reviewing the implementing, trust me, no matter root table or
master local region, there are no big differences on the implementing steps.
Thanks.
> POC: hbase:meta,,1 as ROOT
> --------------------------
>
> Key: HBASE-25761
> URL: https://issues.apache.org/jira/browse/HBASE-25761
> Project: HBase
> Issue Type: Sub-task
> Reporter: Michael Stack
> Assignee: Francis Christopher Liu
> Priority: Major
>
> One of the proposals up in the split-meta design doc suggests a
> sleight-of-hand where the current hard-coded hbase:meta,,1 Region is
> leveraged to serve as first Region of a split hbase:meta but also does
> double-duty as 'ROOT'. This suggestion was put aside as a complicating
> recursion in chat but then Francis noticed on a re-read of the BigTable
> paper, that this is how they describe they do 'ROOT': "The root tablet is
> just the first tablet in the METADATA table, but is treated specially -- it
> is never split..."
> This issue is for playing around with this notion to see what the problems
> are so can do a better description of this approach here, in the design:
> https://docs.google.com/document/d/11ChsSb2LGrSzrSJz8pDCAw5IewmaMV0ZDN1LrMkAj4s/edit?ts=606c120f#heading=h.ikbhxlcthjle
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
