message: core: disable pacing when RTT is less than 2ms
diff: @@ -36,6 +36,10 @@ const SLOW_START_N: Fraction = Fraction(2, 1); // 2/1 = 2.00
  // TODO: Determine an appropriate value for this that balances improvements to 2nd packet loss and delay
  const INITIAL_INTERVAL: Duration = Duration::from_millis(0);
  +/// low RTT networks should not be using pacing since it'll take longer to wake up from
  +/// a timer than it would to deliver a packet
  +const MINIMUM_PACING_RTT: Duration = Duration::from_millis(2);
  +
  /// A packet pacer that returns departure times that evenly distribute bursts of packets over time
  #[derive(Clone, Debug, Default)]
  pub struct Pacer {
  @@ -57,6 +61,10 @@ impl Pacer {
  max_datagram_size: u16,
  slow_start: bool,
  ) {
  + if rtt_estimator.smoothed_rtt() < MINIMUM_PACING_RTT {
  + return;
  + }
  +
  if self.capacity == 0 {
  if let Some(next_packet_departure_time) = self.next_packet_departure_time {
  let interval = Self::interval(
  