There are many retries when i am using graceful_stop.sh to shutdown region server after using regroup, because the target server in a different rsgroup. This makes it slow to graceful shutdown a regionserver. So i think that region_mover.rb should only choose same rsgroup servers as target servers.
Region mover is implemented by jruby in hbase1.x and is implemented by java in hbase2.x . I tried to modify the RegionMover.java class to use the same logic in hbase2.x, but mvn package failed due to hbase-server module and hbase-rsgroup moudle needed to depend on each other, then maven throw a "The projects in the reactor contain a cyclic reference". I couldn't solve it.So I just uploaded patch for hbase1.x .