High Client Stale Connection Performance Issues

[CJBuchel]

The rust server checks all clients currently connected to determine if there are any stale connections or not.
May cause performance drops, but it's unlikely. Putting it here for future me.

The specific code I reference is

// Client timestamp update fairing
pub struct ClientTimestampUpdate;
#[rocket::async_trait]
impl Fairing for ClientTimestampUpdate {
  fn info(&self) -> Info {
    Info {
      name: "Update client timestamp",
      kind: Kind::Request
    }
  }

  async fn on_request(&self, request: &mut Request<'_>, _: &mut Data<'_>) {
    let path_segments: Vec<String> = request.uri().path().split('/').map(|s| s.to_string()).collect();
    // Assuming that UUID is always the last segment
    if let Some(uuid) = path_segments.last() {
      if Uuid::parse_str(uuid).is_ok() { // check if it is a valid uuid
        if let Some(state) = request.rocket().state::<TmsClients>() {
          with_clients_write(&state, |client_map| {
            if let Some(client) = client_map.get_mut(uuid) {
              client.last_timestamp = std::time::SystemTime::now();
            }
    
            // Check all clients for stale connections
            let current_time = std::time::SystemTime::now();
            let mut stale_clients: Vec<String> = Vec::new();
            for (id, client) in client_map.iter() {
              if let Ok(duration) = current_time.duration_since(client.last_timestamp) {
                if duration.as_secs() > (5 * 60) { // 5 mins
                  stale_clients.push(id.to_string());
                }
              }
            }
    
            // remove oldest stale clients if there are more than 100
            let num_allowed_stale_clients = 100;
            if stale_clients.len() > num_allowed_stale_clients {
              stale_clients.sort_by(|a, b| {
                client_map[a].last_timestamp.cmp(&client_map[b].last_timestamp)
              });
    
              for i in 0..(stale_clients.len() - num_allowed_stale_clients) {
                let id = stale_clients[i].clone();
                client_map.remove(&id);
              }
            }
          }).unwrap();
  
        }
      }
    }
  }
}