}
}

// watermark tracks requests being executed (not waiting in a queue)
var watermark = &requestWatermark{
	phase: metrics.ExecutingPhase,
}

// startWatermarkMaintenance starts the goroutines to observe and maintain the specified watermark.
func startWatermarkMaintenance(watermark *requestWatermark, stopCh <-chan struct{}) {
	// Periodically update the inflight usage metric.
	go wait.Until(func() {
		watermark.lock.Lock()

// priority-and-fairness requests.
func StartPriorityAndFairnessWatermarkMaintenance(stopCh <-chan struct{}) {
	startWatermarkMaintenance(watermark, stopCh)
	startWatermarkMaintenance(waitingMark, stopCh)
}

func setResponseHeaders(classification *PriorityAndFairnessClassification, w http.ResponseWriter) {
	if classification == nil {
		return
	}