Documentation

Index

Constants

View Source
const CloudVolumeCreatedForClaimNameTag = "kubernetes.io/created-for/pvc/name"

    CloudVolumeCreatedForClaimNameTag is a name of a tag attached to a real volume in cloud (e.g. AWS EBS or GCE PD) with name of a persistent volume claim used to create this volume.

    View Source
    const CloudVolumeCreatedForClaimNamespaceTag = "kubernetes.io/created-for/pvc/namespace"

      CloudVolumeCreatedForClaimNamespaceTag is a name of a tag attached to a real volume in cloud (e.g. AWS EBS or GCE PD) with namespace of a persistent volume claim used to create this volume.

      View Source
      const CloudVolumeCreatedForVolumeNameTag = "kubernetes.io/created-for/pv/name"

        CloudVolumeCreatedForVolumeNameTag is a name of a tag attached to a real volume in cloud (e.g. AWS EBS or GCE PD) with name of appropriate Kubernetes persistent volume .

        View Source
        const VolumeSchedulerSubsystem = "scheduler_volume"

          VolumeSchedulerSubsystem - subsystem name used by scheduler

          Variables

          View Source
          var (
          	VolumeBindingRequestSchedulerBinderCache = prometheus.NewCounterVec(
          		prometheus.CounterOpts{
          			Subsystem: VolumeSchedulerSubsystem,
          			Name:      "binder_cache_requests_total",
          			Help:      "Total number for request volume binding cache",
          		},
          		[]string{"operation"},
          	)
          	VolumeSchedulingStageLatency = prometheus.NewHistogramVec(
          		prometheus.HistogramOpts{
          			Subsystem: VolumeSchedulerSubsystem,
          			Name:      "scheduling_duration_seconds",
          			Help:      "Volume scheduling stage latency",
          			Buckets:   prometheus.ExponentialBuckets(1000, 2, 15),
          		},
          		[]string{"operation"},
          	)
          	VolumeSchedulingStageFailed = prometheus.NewCounterVec(
          		prometheus.CounterOpts{
          			Subsystem: VolumeSchedulerSubsystem,
          			Name:      "scheduling_stage_error_total",
          			Help:      "Volume scheduling stage error count",
          		},
          		[]string{"operation"},
          	)
          )

          Functions

          func GetBindVolumeToClaim

          func GetBindVolumeToClaim(volume *v1.PersistentVolume, claim *v1.PersistentVolumeClaim) (*v1.PersistentVolume, bool, error)

            GetBindVolumeToClaim returns a new volume which is bound to given claim. In addition, it returns a bool which indicates whether we made modification on original volume.

            func IsDelayBindingMode

            func IsDelayBindingMode(claim *v1.PersistentVolumeClaim, classLister storagelisters.StorageClassLister) (bool, error)

              IsDelayBindingMode checks if claim is in delay binding mode.

              func IsVolumeBoundToClaim

              func IsVolumeBoundToClaim(volume *v1.PersistentVolume, claim *v1.PersistentVolumeClaim) bool

                IsVolumeBoundToClaim returns true, if given volume is pre-bound or bound to specific claim. Both claim.Name and claim.Namespace must be equal. If claim.UID is present in volume.Spec.ClaimRef, it must be equal too.

                func NewAssumeCache

                func NewAssumeCache(informer cache.SharedIndexInformer, description, indexName string, indexFunc cache.IndexFunc) *assumeCache

                func RegisterVolumeSchedulingMetrics

                func RegisterVolumeSchedulingMetrics()

                  RegisterVolumeSchedulingMetrics is used for scheduler, because the volume binding cache is a library used by scheduler process.

                  Types

                  type AssumeCache

                  type AssumeCache interface {
                  	// Assume updates the object in-memory only
                  	Assume(obj interface{}) error
                  
                  	// Restore the informer cache's version of the object
                  	Restore(objName string)
                  
                  	// Get the object by name
                  	Get(objName string) (interface{}, error)
                  
                  	// Get the API object by name
                  	GetAPIObj(objName string) (interface{}, error)
                  
                  	// List all the objects in the cache
                  	List(indexObj interface{}) []interface{}
                  }

                    AssumeCache is a cache on top of the informer that allows for updating objects outside of informer events and also restoring the informer cache's version of the object. Objects are assumed to be Kubernetes API objects that implement meta.Interface

                    type ControllerParameters

                    type ControllerParameters struct {
                    	KubeClient                clientset.Interface
                    	SyncPeriod                time.Duration
                    	VolumePlugins             []vol.VolumePlugin
                    	Cloud                     cloudprovider.Interface
                    	ClusterName               string
                    	VolumeInformer            coreinformers.PersistentVolumeInformer
                    	ClaimInformer             coreinformers.PersistentVolumeClaimInformer
                    	ClassInformer             storageinformers.StorageClassInformer
                    	PodInformer               coreinformers.PodInformer
                    	NodeInformer              coreinformers.NodeInformer
                    	EventRecorder             record.EventRecorder
                    	EnableDynamicProvisioning bool
                    }

                      ControllerParameters contains arguments for creation of a new PersistentVolume controller.

                      type FakeVolumeBinder

                      type FakeVolumeBinder struct {
                      	AssumeCalled bool
                      	BindCalled   bool
                      	// contains filtered or unexported fields
                      }

                      func NewFakeVolumeBinder

                      func NewFakeVolumeBinder(config *FakeVolumeBinderConfig) *FakeVolumeBinder

                        NewVolumeBinder sets up all the caches needed for the scheduler to make topology-aware volume binding decisions.

                        func (*FakeVolumeBinder) AssumePodVolumes

                        func (b *FakeVolumeBinder) AssumePodVolumes(assumedPod *v1.Pod, nodeName string) (bool, error)

                        func (*FakeVolumeBinder) BindPodVolumes

                        func (b *FakeVolumeBinder) BindPodVolumes(assumedPod *v1.Pod) error

                        func (*FakeVolumeBinder) FindPodVolumes

                        func (b *FakeVolumeBinder) FindPodVolumes(pod *v1.Pod, node *v1.Node) (unboundVolumesSatisfied, boundVolumesSatsified bool, err error)

                        func (*FakeVolumeBinder) GetBindingsCache

                        func (b *FakeVolumeBinder) GetBindingsCache() PodBindingCache

                        type FakeVolumeBinderConfig

                        type FakeVolumeBinderConfig struct {
                        	AllBound             bool
                        	FindUnboundSatsified bool
                        	FindBoundSatsified   bool
                        	FindErr              error
                        	AssumeErr            error
                        	BindErr              error
                        }

                        type PVAssumeCache

                        type PVAssumeCache interface {
                        	AssumeCache
                        
                        	GetPV(pvName string) (*v1.PersistentVolume, error)
                        	GetAPIPV(pvName string) (*v1.PersistentVolume, error)
                        	ListPVs(storageClassName string) []*v1.PersistentVolume
                        }

                          PVAssumeCache is a AssumeCache for PersistentVolume objects

                          func NewPVAssumeCache

                          func NewPVAssumeCache(informer cache.SharedIndexInformer) PVAssumeCache

                          type PVCAssumeCache

                          type PVCAssumeCache interface {
                          	AssumeCache
                          
                          	// GetPVC returns the PVC from the cache with given pvcKey.
                          	// pvcKey is the result of MetaNamespaceKeyFunc on PVC obj
                          	GetPVC(pvcKey string) (*v1.PersistentVolumeClaim, error)
                          	GetAPIPVC(pvcKey string) (*v1.PersistentVolumeClaim, error)
                          }

                            PVCAssumeCache is a AssumeCache for PersistentVolumeClaim objects

                            func NewPVCAssumeCache

                            func NewPVCAssumeCache(informer cache.SharedIndexInformer) PVCAssumeCache

                            type PersistentVolumeController

                            type PersistentVolumeController struct {
                            	NodeLister       corelisters.NodeLister
                            	NodeListerSynced cache.InformerSynced
                            	// contains filtered or unexported fields
                            }

                              PersistentVolumeController is a controller that synchronizes PersistentVolumeClaims and PersistentVolumes. It starts two cache.Controllers that watch PersistentVolume and PersistentVolumeClaim changes.

                              func NewController

                                NewController creates a new PersistentVolume controller

                                func (*PersistentVolumeController) DeleteServiceAccountTokenFunc

                                func (ctrl *PersistentVolumeController) DeleteServiceAccountTokenFunc() func(types.UID)

                                func (*PersistentVolumeController) GetCloudProvider

                                func (ctrl *PersistentVolumeController) GetCloudProvider() cloudprovider.Interface

                                func (*PersistentVolumeController) GetConfigMapFunc

                                func (ctrl *PersistentVolumeController) GetConfigMapFunc() func(namespace, name string) (*v1.ConfigMap, error)

                                func (*PersistentVolumeController) GetEventRecorder

                                func (ctrl *PersistentVolumeController) GetEventRecorder() record.EventRecorder

                                func (*PersistentVolumeController) GetExec

                                func (adc *PersistentVolumeController) GetExec(pluginName string) mount.Exec

                                func (*PersistentVolumeController) GetHostIP

                                func (ctrl *PersistentVolumeController) GetHostIP() (net.IP, error)

                                func (*PersistentVolumeController) GetHostName

                                func (ctrl *PersistentVolumeController) GetHostName() string

                                func (*PersistentVolumeController) GetKubeClient

                                func (ctrl *PersistentVolumeController) GetKubeClient() clientset.Interface

                                func (*PersistentVolumeController) GetMounter

                                func (ctrl *PersistentVolumeController) GetMounter(pluginName string) mount.Interface

                                func (*PersistentVolumeController) GetNodeAllocatable

                                func (ctrl *PersistentVolumeController) GetNodeAllocatable() (v1.ResourceList, error)

                                func (*PersistentVolumeController) GetNodeLabels

                                func (ctrl *PersistentVolumeController) GetNodeLabels() (map[string]string, error)

                                func (*PersistentVolumeController) GetNodeName

                                func (ctrl *PersistentVolumeController) GetNodeName() types.NodeName

                                func (*PersistentVolumeController) GetPluginDir

                                func (ctrl *PersistentVolumeController) GetPluginDir(pluginName string) string

                                func (*PersistentVolumeController) GetPodPluginDir

                                func (ctrl *PersistentVolumeController) GetPodPluginDir(podUID types.UID, pluginName string) string

                                func (*PersistentVolumeController) GetPodVolumeDeviceDir

                                func (ctrl *PersistentVolumeController) GetPodVolumeDeviceDir(ppodUID types.UID, pluginName string) string

                                func (*PersistentVolumeController) GetPodVolumeDir

                                func (ctrl *PersistentVolumeController) GetPodVolumeDir(podUID types.UID, pluginName string, volumeName string) string

                                func (*PersistentVolumeController) GetPodsDir

                                func (ctrl *PersistentVolumeController) GetPodsDir() string

                                func (*PersistentVolumeController) GetSecretFunc

                                func (ctrl *PersistentVolumeController) GetSecretFunc() func(namespace, name string) (*v1.Secret, error)

                                func (*PersistentVolumeController) GetServiceAccountTokenFunc

                                func (ctrl *PersistentVolumeController) GetServiceAccountTokenFunc() func(_, _ string, _ *authenticationv1.TokenRequest) (*authenticationv1.TokenRequest, error)

                                func (*PersistentVolumeController) GetSubpather

                                func (ctrl *PersistentVolumeController) GetSubpather() subpath.Interface

                                func (*PersistentVolumeController) GetVolumeDevicePluginDir

                                func (ctrl *PersistentVolumeController) GetVolumeDevicePluginDir(pluginName string) string

                                func (*PersistentVolumeController) NewWrapperMounter

                                func (ctrl *PersistentVolumeController) NewWrapperMounter(volName string, spec vol.Spec, pod *v1.Pod, opts vol.VolumeOptions) (vol.Mounter, error)

                                func (*PersistentVolumeController) NewWrapperUnmounter

                                func (ctrl *PersistentVolumeController) NewWrapperUnmounter(volName string, spec vol.Spec, podUID types.UID) (vol.Unmounter, error)

                                func (*PersistentVolumeController) Run

                                func (ctrl *PersistentVolumeController) Run(stopCh <-chan struct{})

                                  Run starts all of this controller's control loops

                                  type PodBindingCache

                                  type PodBindingCache interface {
                                  	// UpdateBindings will update the cache with the given bindings for the
                                  	// pod and node.
                                  	UpdateBindings(pod *v1.Pod, node string, bindings []*bindingInfo, provisionings []*v1.PersistentVolumeClaim)
                                  
                                  	// ClearBindings will clear the cached bindings for the given pod and node.
                                  	ClearBindings(pod *v1.Pod, node string)
                                  
                                  	// GetBindings will return the cached bindings for the given pod and node.
                                  	// A nil return value means that the entry was not found. An empty slice
                                  	// means that no binding operations are needed.
                                  	GetBindings(pod *v1.Pod, node string) []*bindingInfo
                                  
                                  	// A nil return value means that the entry was not found. An empty slice
                                  	// means that no provisioning operations are needed.
                                  	GetProvisionedPVCs(pod *v1.Pod, node string) []*v1.PersistentVolumeClaim
                                  
                                  	// GetDecisions will return all cached decisions for the given pod.
                                  	GetDecisions(pod *v1.Pod) nodeDecisions
                                  
                                  	// DeleteBindings will remove all cached bindings and provisionings for the given pod.
                                  	// TODO: separate the func if it is needed to delete bindings/provisionings individually
                                  	DeleteBindings(pod *v1.Pod)
                                  }

                                    podBindingCache stores PV binding decisions per pod per node. Pod entries are removed when the Pod is deleted or updated to no longer be schedulable.

                                    func NewPodBindingCache

                                    func NewPodBindingCache() PodBindingCache

                                    type SchedulerVolumeBinder

                                    type SchedulerVolumeBinder interface {
                                    	// FindPodVolumes checks if all of a Pod's PVCs can be satisfied by the node.
                                    	//
                                    	// If a PVC is bound, it checks if the PV's NodeAffinity matches the Node.
                                    	// Otherwise, it tries to find an available PV to bind to the PVC.
                                    	//
                                    	// It returns true if all of the Pod's PVCs have matching PVs or can be dynamic provisioned,
                                    	// and returns true if bound volumes satisfy the PV NodeAffinity.
                                    	//
                                    	// This function is called by the volume binding scheduler predicate and can be called in parallel
                                    	FindPodVolumes(pod *v1.Pod, node *v1.Node) (unboundVolumesSatisified, boundVolumesSatisfied bool, err error)
                                    
                                    	// AssumePodVolumes will:
                                    	// 1. Take the PV matches for unbound PVCs and update the PV cache assuming
                                    	// that the PV is prebound to the PVC.
                                    	// 2. Take the PVCs that need provisioning and update the PVC cache with related
                                    	// annotations set.
                                    	//
                                    	// It returns true if all volumes are fully bound
                                    	//
                                    	// This function will modify assumedPod with the node name.
                                    	// This function is called serially.
                                    	AssumePodVolumes(assumedPod *v1.Pod, nodeName string) (allFullyBound bool, err error)
                                    
                                    	// BindPodVolumes will:
                                    	// 1. Initiate the volume binding by making the API call to prebind the PV
                                    	// to its matching PVC.
                                    	// 2. Trigger the volume provisioning by making the API call to set related
                                    	// annotations on the PVC
                                    	// 3. Wait for PVCs to be completely bound by the PV controller
                                    	//
                                    	// This function can be called in parallel.
                                    	BindPodVolumes(assumedPod *v1.Pod) error
                                    
                                    	// GetBindingsCache returns the cache used (if any) to store volume binding decisions.
                                    	GetBindingsCache() PodBindingCache
                                    }

                                      SchedulerVolumeBinder is used by the scheduler to handle PVC/PV binding and dynamic provisioning. The binding decisions are integrated into the pod scheduling workflow so that the PV NodeAffinity is also considered along with the pod's other scheduling requirements.

                                      This integrates into the existing default scheduler workflow as follows: 1. The scheduler takes a Pod off the scheduler queue and processes it serially:

                                      a. Invokes all predicate functions, parallelized across nodes.  FindPodVolumes() is invoked here.
                                      b. Invokes all priority functions.  Future/TBD
                                      c. Selects the best node for the Pod.
                                      d. Cache the node selection for the Pod. AssumePodVolumes() is invoked here.
                                         i.  If PVC binding is required, cache in-memory only:
                                             * For manual binding: update PV objects for prebinding to the corresponding PVCs.
                                             * For dynamic provisioning: update PVC object with a selected node from c)
                                             * For the pod, which PVCs and PVs need API updates.
                                         ii. Afterwards, the main scheduler caches the Pod->Node binding in the scheduler's pod cache,
                                             This is handled in the scheduler and not here.
                                      e. Asynchronously bind volumes and pod in a separate goroutine
                                          i.  BindPodVolumes() is called first. It makes all the necessary API updates and waits for
                                              PV controller to fully bind and provision the PVCs. If binding fails, the Pod is sent
                                              back through the scheduler.
                                          ii. After BindPodVolumes() is complete, then the scheduler does the final Pod->Node binding.
                                      

                                      2. Once all the assume operations are done in d), the scheduler processes the next Pod in the scheduler queue

                                      while the actual binding operation occurs in the background.
                                      

                                      func NewVolumeBinder

                                        NewVolumeBinder sets up all the caches needed for the scheduler to make volume binding decisions.

                                        Directories

                                        Path Synopsis