pub async fn push_score_fetch_statistic(&self, score: Score) -> (u32, ServerStatData) {
        let (updated_score, data) = {
            let mut stat = self.stat_data.lock().await;
            (stat.push_score(score), *stat.data())
        };
        self.score.store(updated_score, Ordering::Release);
        (updated_score, data)
    }
Append a `Score` into statistic and recalculate score of the server
crates/shadowsocks-service/src/local/loadbalancing/server_data.rs