[
https://issues.apache.org/jira/browse/HBASE-5510?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13221537#comment-13221537
]
Anoop Sam John commented on HBASE-5510:
---------------------------------------
@Ted
Thanks for your reply. R1-S1 mapping can be found out using the start and
end keys of both these regions. Our design will be so that whenever we see S1
when will be able to judge which R1 is its buddy.. am I clear to you? But now
the issue is randomAssignment() will not reveal the region for which the
selection is happening now. If we can get this we will be able to do our
business scenario using our LB.. :)
@Ram : Thanks for the explanation comment.
Thanks
> Change in LB.randomAssignment(List<ServerName> servers) API
> -----------------------------------------------------------
>
> Key: HBASE-5510
> URL: https://issues.apache.org/jira/browse/HBASE-5510
> Project: HBase
> Issue Type: Improvement
> Affects Versions: 0.92.0
> Reporter: Anoop Sam John
> Assignee: ramkrishna.s.vasudevan
>
> In LB there is randomAssignment(List<ServerName servers>) API which will be
> used by AM to assign
> a region from a down RS. [This will be also used in other cases like call to
> assign() API from client]
> I feel it would be better to pass the HRegionInfo also into this method.
> When the LB making a choice for a region
> assignment, when one RS is down, it would be nice that the LB knows for
> which region it is doing this server selection.
> +Scenario+
> While one RS down, we wanted the regions to get moved to other RSs but a set
> of regions stay together. We are having custom load balancer but with the
> current way of LB interface this is not possible. Another way is I can allow
> a random assignment of the regions at the RS down time. Later with a cluster
> balance I can balance the regions as I need. But this might make regions
> assign 1st to one RS and then again move to another. Also for some time
> period my business use case can not get satisfied.
> Also I have seen some issue in JIRA which speaks about making sure that Root
> and META regions always sit in some specific RSs. With the current LB API
> this wont be possible in future.
--
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
