policy

Documentation

Index

• Constants
• func ActivePolicy() string
• func ConstraintToString(value Constraint) string
• func Register(name, description string, create CreateFn) error
• type AvailablePolicy
  • func AvailablePolicies() []*AvailablePolicy
• type Backend
• type BackendOptions
• type Constraint
• type ConstraintSet
  • func (cs ConstraintSet) MarshalJSON() ([]byte, error)
  • func (cs *ConstraintSet) String() string
  • func (cs *ConstraintSet) UnmarshalJSON(raw []byte) error
• type CreateFn
• type Domain
• type Metrics
• type Options
• type Policy
  • func NewPolicy(cache cache.Cache, o *Options) (Policy, error)
• type SendEventFn

Constants

const (
	// NonePolicy is the name of our no-op policy.
	NonePolicy = "none"
	// DefaultPolicy is the name of our default policy.
	DefaultPolicy = NonePolicy
	// ConfigPath is the configuration module path for the generic policy layer.
	ConfigPath = "policy"
)

const (
	// ExportedResources is the basename of the file container resources are exported to.
	ExportedResources = "resources.sh"
	// ExportSharedCPUs is the shell variable used to export shared container CPUs.
	ExportSharedCPUs = "SHARED_CPUS"
	// ExportIsolatedCPUs is the shell variable used to export isolated container CPUs.
	ExportIsolatedCPUs = "ISOLATED_CPUS"
	// ExportExclusiveCPUs is the shell variable used to export exclusive container CPUs.
	ExportExclusiveCPUs = "EXCLUSIVE_CPUS"
)

Functions

func ActivePolicy

func ActivePolicy() string

ActivePolicy returns the name of the policy to be activated.

func ConstraintToString

func ConstraintToString(value Constraint) string

ConstraintToString returns the given constraint as a string.

func Register

func Register(name, description string, create CreateFn) error

Register registers a policy backend.

Types

type AvailablePolicy

type AvailablePolicy struct {
	// Name is the name of the policy.
	Name string
	// Description is a short description of the policy.
	Description string
}

AvailablePolicy describes an available policy.

func AvailablePolicies

func AvailablePolicies() []*AvailablePolicy

AvailablePolicies returns the available policies and their descriptions.

type Backend

type Backend interface {
	// Name gets the well-known name of this policy.
	Name() string
	// Description gives a verbose description about the policy implementation.
	Description() string
	// Start up and sycnhronizes the policy, using the given cache and resource constraints.
	Start([]cache.Container, []cache.Container) error
	// Sync synchronizes the policy, allocating/releasing the given containers.
	Sync([]cache.Container, []cache.Container) error
	// AllocateResources allocates resources to/for a container.
	AllocateResources(cache.Container) error
	// ReleaseResources release resources of a container.
	ReleaseResources(cache.Container) error
	// UpdateResources updates resource allocations of a container.
	UpdateResources(cache.Container) error
	// Rebalance tries an optimal allocation of resources for the current container.
	Rebalance() (bool, error)
	// HandleEvent processes the given event. The returned boolean indicates whether
	// changes have been made to any of the containers while handling the event.
	HandleEvent(*events.Policy) (bool, error)
	// ExportResourceData provides resource data to export for the container.
	ExportResourceData(cache.Container) map[string]string
	// Introspect provides data for external introspection.
	Introspect(*introspect.State)
	// DescribeMetrics generates policy-specific prometheus metrics data descriptors.
	DescribeMetrics() []*prometheus.Desc
	// PollMetrics provides policy metrics for monitoring.
	PollMetrics() Metrics
	// CollectMetrics generates prometheus metrics from cached/polled policy-specific metrics data.
	CollectMetrics(Metrics) ([]prometheus.Metric, error)
}

Backend is the policy (decision making logic) interface exposed by implementations.

A backends operates in a set of policy domains. Currently each policy domain corresponds to some particular hardware resource (CPU, memory, cache, etc).

type BackendOptions

type BackendOptions struct {
	// System provides system/HW/topology information
	System system.System
	// System state/cache
	Cache cache.Cache
	// Resource availibility constraint
	Available ConstraintSet
	// Resource reservation constraint
	Reserved ConstraintSet
	// Client interface to cri-resmgr agent
	AgentCli agent.Interface
	// SendEvent is the function for delivering events up to the resource manager.
	SendEvent SendEventFn
}

BackendOptions describes the options for a policy backend instance

type Constraint

type Constraint interface{}

Constraint describes constraint of one hardware domain

type ConstraintSet

type ConstraintSet map[Domain]Constraint

ConstraintSet describes, per hardware domain, the resources available for a policy.

func (ConstraintSet) MarshalJSON

func (cs ConstraintSet) MarshalJSON() ([]byte, error)

MarshalJSON implements JSON marshalling for ConstraintSets.

func (*ConstraintSet) String

func (cs *ConstraintSet) String() string

func (*ConstraintSet) UnmarshalJSON

func (cs *ConstraintSet) UnmarshalJSON(raw []byte) error

UnmarshalJSON implements JSON unmarshalling for ConstraintSets.

type CreateFn

type CreateFn func(*BackendOptions) Backend

CreateFn is the type for functions used to create a policy instance.

type Domain

type Domain string

Domain represents a hardware resource domain that can be policied by a backend.

const (
	// DomainCPU is the CPU resource domain.
	DomainCPU Domain = "CPU"
	// DomainMemory is the memory resource domain.
	DomainMemory Domain = "Memory"
	// DomainHugePage is the hugepages resource domain.
	DomainHugePage Domain = "HugePages"
	// DomainCache is the CPU cache resource domain.
	DomainCache Domain = "Cache"
	// DomainMemoryBW is the memory resource bandwidth.
	DomainMemoryBW Domain = "MBW"
)

type Metrics

type Metrics interface{}

type Options

type Options struct {
	// Client interface to cri-resmgr agent
	AgentCli agent.Interface
	// SendEvent is the function for delivering events back to the resource manager.
	SendEvent SendEventFn
}

Options describes policy options

type Policy

type Policy interface {
	// Start starts up policy, prepare for serving resource management requests.
	Start([]cache.Container, []cache.Container) error
	// Sync synchronizes the state of the active policy.
	Sync([]cache.Container, []cache.Container) error
	// AllocateResources allocates resources to a container.
	AllocateResources(cache.Container) error
	// ReleaseResources releases resources of a container.
	ReleaseResources(cache.Container) error
	// UpdateResources updates resource allocations of a container.
	UpdateResources(cache.Container) error
	// Rebalance tries to find an optimal allocation of resources for the current containers.
	Rebalance() (bool, error)
	// HandleEvent passes on the given event to the active policy. The returned boolean
	// indicates whether changes have been made to any of the containers while handling
	// the event.
	HandleEvent(*events.Policy) (bool, error)
	// ExportResourceData exports/updates resource data for the container.
	ExportResourceData(cache.Container)
	// Introspect provides data for external introspection.
	Introspect() *introspect.State
	// DescribeMetrics generates policy-specific prometheus metrics data descriptors.
	DescribeMetrics() []*prometheus.Desc
	// PollMetrics provides policy metrics for monitoring.
	PollMetrics() Metrics
	// CollectMetrics generates prometheus metrics from cached/polled policy-specific metrics data.
	CollectMetrics(Metrics) ([]prometheus.Metric, error)
}

Policy is the exposed interface for container resource allocations decision making.

func NewPolicy

func NewPolicy(cache cache.Cache, o *Options) (Policy, error)

NewPolicy creates a policy instance using the selected backend.

type SendEventFn

type SendEventFn func(interface{}) error

SendEventFn is the type for a function to send events back to the resource manager.