code: public static synchronized String getLocalHostMetricName(int timeoutMs) {
      if (sLocalHostMetricName != null) {
        return sLocalHostMetricName;
      }
      sLocalHostMetricName = getLocalHostName(timeoutMs).replace('.', '_');
      return sLocalHostMetricName;
    }
docs: Gets a local hostname for the host this JVM is running on with '.' replaced with '_' for
  metrics usage.
  
  @param timeoutMs Timeout in milliseconds to use for checking that a possible local host is
  reachable
  @return the metrics system friendly local host name