@Override
  protected void chore() {
    try {
      master.normalizeRegions(new NormalizeTableFilterParams.Builder().build(), false);
    } catch (IOException e) {
      LOG.error("Failed to normalize regions.", e);
    }
  }
Chore that will periodically call
{@link HMaster#normalizeRegions(NormalizeTableFilterParams, boolean)}.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/normalizer/RegionNormalizerChore.java