message: RTT is millisecond
diff: @@ -60,7 +60,7 @@ impl ServerStatisticData {
  fn score(&self) -> u64 {
  // Normalize rtt
  - let nrtt = self.rtt as f64 / DEFAULT_CHECK_TIMEOUT_SEC as f64;
  + let nrtt = self.rtt as f64 / (DEFAULT_CHECK_TIMEOUT_SEC * 1000) as f64;
  // Score = norm_lat + prop_err
  //
  