eviction

Documentation

Index

• Variables
• type Config
  • func NewConfig(yamlContent []byte) (Config, error)
• type Signal
• type Threshold
• type ThresholdMap
  • func (m ThresholdMap) GetImageFsAvailable() *Threshold
  • func (m ThresholdMap) GetMemoryAvailable() *Threshold
  • func (m ThresholdMap) GetNodeFsAvailable() *Threshold
  • func (m ThresholdMap) GetNodeFsInodesFree() *Threshold
• type ThresholdOperator
• type ThresholdValue

Variables

var (
	// DefaultEvictionHard includes default options for kubelet hard eviction
	// ref: https://github.com/kubernetes/kubernetes/blob/ec39cc2eafffa51b3267e3bd64fbd2598c0db94d/pkg/kubelet/apis/config/v1beta1/defaults_linux.go#L21
	DefaultEvictionHard = map[string]string{
		string(SignalMemoryAvailable):  "100Mi",
		string(SignalNodeFsAvailable):  "10%",
		string(SignalNodeFsInodesFree): "5%",
		string(SignalImageFsAvailable): "15%",
	}
)

var OpForSignal = map[Signal]ThresholdOperator{
	SignalMemoryAvailable:   OpLessThan,
	SignalNodeFsAvailable:   OpLessThan,
	SignalNodeFsInodesFree:  OpLessThan,
	SignalImageFsAvailable:  OpLessThan,
	SignalImageFsInodesFree: OpLessThan,
	SignalPIDAvailable:      OpLessThan,
}

OpForSignal maps Signals to ThresholdOperators. Today, the only supported operator is "LessThan".

Types

type Config

type Config interface {
	GetHard() ThresholdMap
	String() string
}

Config holds information about how eviction is configured.

func NewConfig

func NewConfig(yamlContent []byte) (Config, error)

type Signal

type Signal string

Signal defines a signal that can trigger eviction of pods on a node.

const (
	// SignalMemoryAvailable is memory available (i.e. capacity - workingSet), in bytes.
	SignalMemoryAvailable Signal = "memory.available"
	// SignalNodeFsAvailable is amount of storage available on filesystem that kubelet uses for volumes, daemon logs, etc.
	SignalNodeFsAvailable Signal = "nodefs.available"
	// SignalNodeFsInodesFree is amount of storage available on filesystem that container runtime uses for storing images and container writable layers.
	SignalNodeFsInodesFree Signal = "nodefs.inodesFree"
	// SignalImageFsAvailable is amount of storage available on filesystem that container runtime uses for storing images and container writable layers.
	SignalImageFsAvailable Signal = "imagefs.available"
	// SignalImageFsInodesFree is amount of inodes available on filesystem that container runtime uses for storing images and container writable layers.
	SignalImageFsInodesFree Signal = "imagefs.inodesFree"
	// SignalAllocatableMemoryAvailable is amount of memory available for pod allocation (i.e. allocatable - workingSet (of pods), in bytes)
	// SignalAllocatableMemoryAvailable Signal = "allocatableMemory.available"
	// SignalPIDAvailable is amount of PID available for pod allocation
	SignalPIDAvailable Signal = "pid.available"
)

type Threshold

type Threshold struct {
	// Signal defines the entity that was measured.
	Signal Signal
	// Operator represents a relationship of a signal to a value.
	Operator ThresholdOperator
	// Value is the threshold the resource is evaluated against.
	Value ThresholdValue
}

Threshold defines a metric for when eviction should occur.

type ThresholdMap

type ThresholdMap map[Signal]*Threshold

func (ThresholdMap) GetImageFsAvailable

func (m ThresholdMap) GetImageFsAvailable() *Threshold

func (ThresholdMap) GetMemoryAvailable

func (m ThresholdMap) GetMemoryAvailable() *Threshold

func (ThresholdMap) GetNodeFsAvailable

func (m ThresholdMap) GetNodeFsAvailable() *Threshold

func (ThresholdMap) GetNodeFsInodesFree

func (m ThresholdMap) GetNodeFsInodesFree() *Threshold

type ThresholdOperator

type ThresholdOperator string

ThresholdOperator is the operator used to express a Threshold.

const (
	// OpLessThan is the operator that expresses a less than operator.
	OpLessThan ThresholdOperator = "LessThan"
)

type ThresholdValue

type ThresholdValue struct {
	// Quantity is a quantity associated with the signal
	Quantity *resource.Quantity
	// Percentage represents the usage percentage over the total resource
	Percentage float32
}

ThresholdValue is a value holder that abstracts literal versus percentage based quantity