@Override
  protected void loadConf(Configuration conf) {
    super.loadConf(conf);
    this.overallSlop = conf.getFloat("hbase.regions.overallSlop", slop);
  }
Pass RegionStates and allow balancer to set the current cluster load.
hbase-balancer/src/main/java/org/apache/hadoop/hbase/master/balancer/SimpleLoadBalancer.java