"k8s.io/klog/v2"
	utilsclock "k8s.io/utils/clock"
)

// PriorityAndFairnessClassification identifies the results of
// classification for API Priority and Fairness
type PriorityAndFairnessClassification struct {
	FlowSchemaName    string
	FlowSchemaUID     apitypes.UID
	PriorityLevelName string
	PriorityLevelUID  apitypes.UID
}

		&compbasemetrics.CounterOpts{
			Namespace:      namespace,
			Subsystem:      subsystem,
			Name:           "rejected_requests_total",
			Help:           "Number of requests rejected by API Priority and Fairness subsystem",
			StabilityLevel: compbasemetrics.BETA,
		},
		[]string{priorityLevel, flowSchema, "reason"},
	)
	apiserverDispatchedRequestsTotal = compbasemetrics.NewCounterVec(
		&compbasemetrics.CounterOpts{

	klog.Info("Starting API Priority and Fairness config controller")
	if ok := cache.WaitForCacheSync(stopCh, cfgCtlr.plInformerSynced, cfgCtlr.fsInformerSynced); !ok {
		return fmt.Errorf("Never achieved initial sync")
	}

	klog.Info("Running API Priority and Fairness config worker")
	go wait.Until(cfgCtlr.runWorker, time.Second, stopCh)

	klog.Info("Running API Priority and Fairness periodic rebalancing process")

	APIListChunking featuregate.Feature = "APIListChunking"

	// owner: @MikeSpreitzer @yue9944882
	// alpha: v1.18
	// beta: v1.20
	// stable: 1.29
	//
	// Enables managing request concurrency with prioritization and fairness at each server.
	// The FeatureGate was introduced in release 1.15 but the feature
	// was not really implemented before 1.18.
	APIPriorityAndFairness featuregate.Feature = "APIPriorityAndFairness"

	// owner: @ilackams

	// Validate webhooks are done in parallel, so max function is used.
	ValidatingWebhookTracker DurationTracker

	// APFQueueWaitTracker tracks the latency incurred by queue wait times
	// from priority & fairness.
	APFQueueWaitTracker DurationTracker

	// StorageTracker tracks the latency incurred inside the storage layer,
	// it accounts for the time it takes to send data to the underlying

 * attempts to {@code take} an element from an empty queue will similarly block.
 *
 * <p>This class supports an optional fairness policy for ordering waiting producer and consumer
 * threads. By default, this ordering is not guaranteed. However, a queue constructed with fairness
 * set to {@code true} grants threads access in FIFO order. Fairness generally decreases throughput
 * but reduces variability and avoids starvation.
 *

 * attempts to {@code take} an element from an empty queue will similarly block.
 *
 * <p>This class supports an optional fairness policy for ordering waiting producer and consumer
 * threads. By default, this ordering is not guaranteed. However, a queue constructed with fairness
 * set to {@code true} grants threads access in FIFO order. Fairness generally decreases throughput
 * but reduces variability and avoids starvation.
 *

  public ReentrantLock newReentrantLock(String lockName) {
    return newReentrantLock(lockName, false);
  }

  /**
   * Creates a {@link ReentrantLock} with the given fairness policy. The {@code lockName} is used in
   * the warning or exception output to help identify the locks involved in the detected deadlock.
   */
  public ReentrantLock newReentrantLock(String lockName, boolean fair) {

		"This and --max-mutating-requests-inflight are summed to determine the server's total concurrency limit "+
		"(which must be positive) if --enable-priority-and-fairness is true. "+
		"Otherwise, this flag limits the maximum number of non-mutating requests in flight, "+
		"or a zero value disables the limit completely.")

  public ReentrantLock newReentrantLock(String lockName) {
    return newReentrantLock(lockName, false);
  }

  /**
   * Creates a {@link ReentrantLock} with the given fairness policy. The {@code lockName} is used in
   * the warning or exception output to help identify the locks involved in the detected deadlock.
   */
  public ReentrantLock newReentrantLock(String lockName, boolean fair) {