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rajeshbabu updated HBASE-10498: ------------------------------- Resolution: Fixed Hadoop Flags: Reviewed Status: Resolved (was: Patch Available) committed to trunk and 0.98. Thank you all for reviews. > Add new APIs to load balancer interface > --------------------------------------- > > Key: HBASE-10498 > URL: https://issues.apache.org/jira/browse/HBASE-10498 > Project: HBase > Issue Type: Improvement > Components: Balancer > Reporter: rajeshbabu > Assignee: rajeshbabu > Fix For: 0.98.1, 0.99.0 > > Attachments: HBASE-10498.patch > > > If a custom load balancer required to maintain region and corresponding > server locations, > we can capture this information when we run any balancer algorithm before > assignment(like random,retain). > But during master startup we will not call any balancer algorithm if a region > already assinged > During split also we open child regions first in RS and then notify to master > through zookeeper. > So split regions information cannot be captured into balancer. > Since balancer has access to master we can get the information from online > regions or region plan data structures in AM. > But some use cases we cannot relay on this information(mainly to maintain > colocation of two tables regions). > So it's better to add some APIs to load balancer to notify balancer when > *region is online or offline*. > These APIs helps a lot to maintain *regions colocation through custom load > balancer* which is very important in secondary indexing. -- This message was sent by Atlassian JIRA (v6.1.5#6160)