public static Map<String, QuotaState> fetchRegionServerQuotas(final Connection connection,
    final List<Get> gets) throws IOException {
    return fetchGlobalQuotas("regionServer", connection, gets, new KeyFromRow<String>() {
      @Override
      public String getKeyFromRow(final byte[] row) {
        assert isRegionServerRowKey(row);
        return getRegionServerFromRowKey(row);
      }

      @Override
      public double getFactor(String s) {
        return 1;
      }
    });
  }
Returns true if the support for quota is enabled
hbase-server/src/main/java/org/apache/hadoop/hbase/quotas/QuotaUtil.java