* The deadline is currently hardcoded. We may make this configurable in the future!
   */
  internal fun sendDegradedPingLater() {
    withLock {
      if (degradedPongsReceived < degradedPingsSent) return // Already awaiting a degraded pong.
      degradedPingsSent++
      degradedPongDeadlineNs = System.nanoTime() + DEGRADED_PONG_TIMEOUT_NS
    }
    writerQueue.execute("$connectionName ping") {
      writePing(false, DEGRADED_PING, 0)