autoscalerconfig

type Config struct {
	// Feature flags.
	EnableScaleToZero bool

	// Target concurrency knobs for different container concurrency configurations.
	ContainerConcurrencyTargetFraction float64
	ContainerConcurrencyTargetDefault  float64
	// TargetUtilization is used for the metrics other than concurrency. This is not
	// configurable now. Customers can override it by specifying
	// autoscaling.knative.dev/targetUtilizationPercentage in Revision annotation.
	// TODO(yanweiguo): Expose this to config-autoscaler configmap and eventually
	// deprecate ContainerConcurrencyTargetFraction.
	TargetUtilization float64
	// RPSTargetDefault is the default target value for requests per second.
	RPSTargetDefault float64
	// NB: most of our computations are in floats, so this is float to avoid casting.
	TargetBurstCapacity float64

	// ActivatorCapacity is the number of the concurrent requests an activator
	// task can accept. This is used in activator subsetting algorithm, to determine
	// the number of activators per revision.
	ActivatorCapacity float64

	// AllowZeroInitialScale indicates whether InitialScale and
	// autoscaling.internal.knative.dev/initialScale are allowed to be set to 0.
	AllowZeroInitialScale bool

	// InitialScale is the cluster-wide default initial revision size for newly deployed
	// services. This can be set to 0 iff AllowZeroInitialScale is true.
	InitialScale int32

	// MinScale is the default min scale for any revision created without an
	// autoscaling.knative.dev/minScale annotation
	MinScale int32

	// MaxScale is the default max scale for any revision created without an
	// autoscaling.knative.dev/maxScale annotation
	MaxScale int32

	// MaxScaleLimit is the maximum allowed MaxScale and `autoscaling.knative.dev/maxScale`
	// annotation value for a revision.
	MaxScaleLimit int32

	// General autoscaler algorithm configuration.
	MaxScaleUpRate           float64
	MaxScaleDownRate         float64
	StableWindow             time.Duration
	PanicWindowPercentage    float64
	PanicThresholdPercentage float64

	// ScaleToZeroGracePeriod is the time we will wait for networking to
	// propagate before scaling down. We may wait less than this if it is safe to
	// do so, for example if the Activator has already been in the path for
	// longer than the window.
	ScaleToZeroGracePeriod time.Duration

	// ScaleToZeroPodRetentionPeriod is the minimum amount of time we will wait
	// before scaling down the last pod.
	ScaleToZeroPodRetentionPeriod time.Duration

	// ScaleDownDelay is the amount of time that must pass at reduced concurrency
	// before a scale-down decision is applied. This can be useful for keeping
	// scaled-up revisions "warm" for a certain period before scaling down. This
	// applies to all scale-down decisions, not just the very last pod.
	// It is independent of ScaleToZeroPodRetentionPeriod, which can be used to
	// add an additional delay to the very last pod, if required.
	ScaleDownDelay time.Duration

	PodAutoscalerClass string
}