[
https://issues.apache.org/jira/browse/HBASE-7932?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13652403#comment-13652403
]
Devaraj Das commented on HBASE-7932:
------------------------------------
bq. Is this comment right?
Nope.. left-over from the previous iteration of the patch
Fixed the comment..
bq. This is probably plain to you but maybe it needs to be drawn out more that
the favored nodes load balancer is but a stepping stone? What we really want is
a stocastic balancer that is favored nodes aware?
Yes, this is something that I'll eventually get to. I can see extending
Stochastic or enhancing Stochastic as options. Need to iron out the specifics.
I am in agreement on the stepping stone part.
bq. Is that a lookup against meta each time we assign a region? If so, won't we
be slowing assign especially if slow meta? Data will be offline longer? Maybe
its not too bad... but probably worth caching favored nodes info or doing the
update out-of-bound with assign? (could be in subsequent patch but I think you
need to note that this look up can take time).
I guess you are referring to the meta table updates in the new table creations
(and the FaceBook guys had done this inline as well) and we talk to the meta
already when we write the HRegionInfos. For the existing tables (that the
master wants to assign on a fresh cluster start), we already have the meta scan
happening (even without the patch) in assignAllUserRegions. Did you mean some
other use case?
I'll update the patch with the new unit tests shortly.
> Do the necessary plumbing for the region locations in META table and send the
> info to the RegionServers
> -------------------------------------------------------------------------------------------------------
>
> Key: HBASE-7932
> URL: https://issues.apache.org/jira/browse/HBASE-7932
> Project: HBase
> Issue Type: Sub-task
> Reporter: Devaraj Das
> Assignee: Devaraj Das
> Priority: Critical
> Fix For: 0.95.1
>
> Attachments: 7932-1.patch, 7932-3.patch, 7932-8.1.patch,
> 7932-8.patch, 7932-simple-2.patch, 7932-simple-with-meta-pb.1.txt,
> 7932-simple-with-meta-pb.2.txt, 7932-wip-2.patch, 7932-wip-3.patch,
> 7932-wip-4.patch, 7932-wip.patch
>
>
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
