const (
	// SchedulerSubsystem - subsystem name used by scheduler
	SchedulerSubsystem = "scheduler"
	// SchedulingLatencyName - scheduler latency metric name
	SchedulingLatencyName = "scheduling_duration_seconds"
	// DeprecatedSchedulingLatencyName - scheduler latency metric name which is deprecated
	DeprecatedSchedulingLatencyName = "scheduling_latency_seconds"

	// OperationLabel - operation label name
	OperationLabel = "operation"

	// PredicateEvaluation - predicate evaluation operation label value
	PredicateEvaluation = "predicate_evaluation"
	// PriorityEvaluation - priority evaluation operation label value
	PriorityEvaluation = "priority_evaluation"
	// PreemptionEvaluation - preemption evaluation operation label value (occurs in case of scheduling fitError).
	PreemptionEvaluation = "preemption_evaluation"
	// Binding - binding operation label value
	Binding = "binding"
)

var (

	// PodScheduleSuccesses counts how many pods were scheduled.
	// This metric will be initialized again in Register() to assure the metric is not no-op metric.
	PodScheduleSuccesses = scheduleAttempts.With(prometheus.Labels{"result": "scheduled"})
	// PodScheduleFailures counts how many pods could not be scheduled.
	// This metric will be initialized again in Register() to assure the metric is not no-op metric.
	PodScheduleFailures = scheduleAttempts.With(prometheus.Labels{"result": "unschedulable"})
	// PodScheduleErrors counts how many pods could not be scheduled due to a scheduler error.
	// This metric will be initialized again in Register() to assure the metric is not no-op metric.
	PodScheduleErrors = scheduleAttempts.With(prometheus.Labels{"result": "error"})
	SchedulingLatency = metrics.NewSummaryVec(
		&metrics.SummaryOpts{
			Subsystem: SchedulerSubsystem,
			Name:      SchedulingLatencyName,
			Help:      "Scheduling latency in seconds split by sub-parts of the scheduling operation",

			MaxAge:         5 * time.Hour,
			StabilityLevel: metrics.ALPHA,
		},
		[]string{OperationLabel},
	)
	DeprecatedSchedulingLatency = metrics.NewSummaryVec(
		&metrics.SummaryOpts{
			Subsystem: SchedulerSubsystem,
			Name:      DeprecatedSchedulingLatencyName,
			Help:      "(Deprecated) Scheduling latency in seconds split by sub-parts of the scheduling operation",

			MaxAge:         5 * time.Hour,
			StabilityLevel: metrics.ALPHA,
		},
		[]string{OperationLabel},
	)
	E2eSchedulingLatency = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "e2e_scheduling_duration_seconds",
			Help:           "E2e scheduling latency in seconds (scheduling algorithm + binding)",
			Buckets:        prometheus.ExponentialBuckets(0.001, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	DeprecatedE2eSchedulingLatency = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "e2e_scheduling_latency_microseconds",
			Help:           "(Deprecated) E2e scheduling latency in microseconds (scheduling algorithm + binding)",
			Buckets:        prometheus.ExponentialBuckets(1000, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	SchedulingAlgorithmLatency = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_duration_seconds",
			Help:           "Scheduling algorithm latency in seconds",
			Buckets:        prometheus.ExponentialBuckets(0.001, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	DeprecatedSchedulingAlgorithmLatency = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_latency_microseconds",
			Help:           "(Deprecated) Scheduling algorithm latency in microseconds",
			Buckets:        prometheus.ExponentialBuckets(1000, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	SchedulingAlgorithmPredicateEvaluationDuration = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_predicate_evaluation_seconds",
			Help:           "Scheduling algorithm predicate evaluation duration in seconds",
			Buckets:        prometheus.ExponentialBuckets(0.001, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	DeprecatedSchedulingAlgorithmPredicateEvaluationDuration = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_predicate_evaluation",
			Help:           "(Deprecated) Scheduling algorithm predicate evaluation duration in microseconds",
			Buckets:        prometheus.ExponentialBuckets(1000, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	SchedulingAlgorithmPriorityEvaluationDuration = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_priority_evaluation_seconds",
			Help:           "Scheduling algorithm priority evaluation duration in seconds",
			Buckets:        prometheus.ExponentialBuckets(0.001, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	DeprecatedSchedulingAlgorithmPriorityEvaluationDuration = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_priority_evaluation",
			Help:           "(Deprecated) Scheduling algorithm priority evaluation duration in microseconds",
			Buckets:        prometheus.ExponentialBuckets(1000, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	SchedulingAlgorithmPremptionEvaluationDuration = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_preemption_evaluation_seconds",
			Help:           "Scheduling algorithm preemption evaluation duration in seconds",
			Buckets:        prometheus.ExponentialBuckets(0.001, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	DeprecatedSchedulingAlgorithmPremptionEvaluationDuration = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "scheduling_algorithm_preemption_evaluation",
			Help:           "(Deprecated) Scheduling algorithm preemption evaluation duration in microseconds",
			Buckets:        prometheus.ExponentialBuckets(1000, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	BindingLatency = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "binding_duration_seconds",
			Help:           "Binding latency in seconds",
			Buckets:        prometheus.ExponentialBuckets(0.001, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	DeprecatedBindingLatency = metrics.NewHistogram(
		&metrics.HistogramOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "binding_latency_microseconds",
			Help:           "(Deprecated) Binding latency in microseconds",
			Buckets:        prometheus.ExponentialBuckets(1000, 2, 15),
			StabilityLevel: metrics.ALPHA,
		},
	)
	PreemptionVictims = metrics.NewGauge(
		&metrics.GaugeOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "pod_preemption_victims",
			Help:           "Number of selected preemption victims",
			StabilityLevel: metrics.ALPHA,
		})
	PreemptionAttempts = metrics.NewCounter(
		&metrics.CounterOpts{
			Subsystem:      SchedulerSubsystem,
			Name:           "total_preemption_attempts",
			Help:           "Total preemption attempts in the cluster till now",
			StabilityLevel: metrics.ALPHA,
		})
)

type MetricRecorder interface {
	Inc()
	Dec()
	Clear()
}

type PendingPodsRecorder struct {
	// contains filtered or unexported fields
}