scheduler

Documentation

Index

• type Binder
• type Config
• type ExtendedPodLister
• type FakeModeler
  • func (f *FakeModeler) AssumePod(pod *api.Pod)
  • func (f *FakeModeler) ForgetPod(pod *api.Pod)
  • func (a *FakeModeler) LockedAction(do func())
• type Scheduler
  • func New(c *Config) *Scheduler
  • func (s *Scheduler) Run()
• type SimpleModeler
  • func NewSimpleModeler(queuedPods, scheduledPods ExtendedPodLister) *SimpleModeler
  • func (s *SimpleModeler) AssumePod(pod *api.Pod)
  • func (s *SimpleModeler) ForgetPod(pod *api.Pod)
  • func (a *SimpleModeler) LockedAction(do func())
  • func (s *SimpleModeler) PodLister() algorithm.PodLister
• type SystemModeler

Types

type Binder

type Binder interface {
	Bind(binding *api.Binding) error
}

Binder knows how to write a binding.

type Config

type Config struct {
	// It is expected that changes made via modeler will be observed
	// by MinionLister and Algorithm.
	Modeler      SystemModeler
	MinionLister scheduler.MinionLister
	Algorithm    scheduler.Scheduler
	Binder       Binder

	// NextPod should be a function that blocks until the next pod
	// is available. We don't use a channel for this, because scheduling
	// a pod may take some amount of time and we don't want pods to get
	// stale while they sit in a channel.
	NextPod func() *api.Pod

	// Error is called if there is an error. It is passed the pod in
	// question, and the error
	Error func(*api.Pod, error)

	// Recorder is the EventRecorder to use
	Recorder record.EventRecorder
}

type ExtendedPodLister

type ExtendedPodLister interface {
	algorithm.PodLister
	Exists(pod *api.Pod) (bool, error)
}

ExtendedPodLister: SimpleModeler needs to be able to check for a pod's existance in addition to listing the pods.

type FakeModeler

type FakeModeler struct {
	AssumePodFunc func(pod *api.Pod)
	ForgetPodFunc func(pod *api.Pod)
	// contains filtered or unexported fields
}

FakeModeler implements the SystemModeler interface.

func (*FakeModeler) AssumePod

func (f *FakeModeler) AssumePod(pod *api.Pod)

AssumePod calls the function variable if it is not nil.

func (*FakeModeler) ForgetPod

func (f *FakeModeler) ForgetPod(pod *api.Pod)

ForgetPod calls the function variable if it is not nil.

func (*FakeModeler) LockedAction

func (a *FakeModeler) LockedAction(do func())

LockedAction serializes calls of whatever is passed as 'do'.

type Scheduler

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

Scheduler watches for new unscheduled pods. It attempts to find minions that they fit on and writes bindings back to the api server.

func New

func New(c *Config) *Scheduler

New returns a new scheduler.

func (*Scheduler) Run

func (s *Scheduler) Run()

Run begins watching and scheduling. It starts a goroutine and returns immediately.

type SimpleModeler

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

SimpleModeler implements the SystemModeler interface with a timed pod cache.

func NewSimpleModeler

func NewSimpleModeler(queuedPods, scheduledPods ExtendedPodLister) *SimpleModeler

NewSimpleModeler returns a new SimpleModeler.

queuedPods: a PodLister that will return pods that have not been scheduled yet.
scheduledPods: a PodLister that will return pods that we know for sure have been scheduled.

func (*SimpleModeler) AssumePod

func (s *SimpleModeler) AssumePod(pod *api.Pod)

func (*SimpleModeler) ForgetPod

func (s *SimpleModeler) ForgetPod(pod *api.Pod)

func (*SimpleModeler) LockedAction

func (a *SimpleModeler) LockedAction(do func())

LockedAction serializes calls of whatever is passed as 'do'.

func (*SimpleModeler) PodLister

func (s *SimpleModeler) PodLister() algorithm.PodLister

PodLister returns a PodLister that will list pods that we think we have scheduled in addition to pods that we know have been scheduled.

type SystemModeler

type SystemModeler interface {
	// AssumePod assumes that the given pod exists in the system.
	// The assumtion should last until the system confirms the
	// assumtion or disconfirms it.
	AssumePod(pod *api.Pod)
	// ForgetPod removes a pod assumtion. (It won't make the model
	// show the absence of the given pod if the pod is in the scheduled
	// pods list!)
	ForgetPod(pod *api.Pod)

	// For serializing calls to Assume/ForgetPod: imagine you want to add
	// a pod iff a bind succeeds, but also remove a pod if it is deleted.
	// TODO: if SystemModeler begins modeling things other than pods, this
	// should probably be parameterized or specialized for pods.
	LockedAction(f func())
}

SystemModeler can help scheduler produce a model of the system that anticipates reality. For example, if scheduler has pods A and B both using hostPort 80, when it binds A to machine M it should not bind B to machine M in the time when it hasn't observed the binding of A take effect yet.

Since the model is only an optimization, it's expected to handle any errors itself without sending them back to the scheduler.