Add local storage (scratch space) allocatable support

cmd/kubelet/app/options/options.go

@@ -291,7 +291,7 @@ func (c *kubeletConfiguration) addFlags(fs *pflag.FlagSet) {
 
 	// Node Allocatable Flags
 	fs.Var(&c.SystemReserved, "system-reserved", "A set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=500Mi) pairs that describe resources reserved for non-kubernetes components. Currently only cpu and memory are supported. See http://kubernetes.io/docs/user-guide/compute-resources for more detail. [default=none]")
-	fs.Var(&c.KubeReserved, "kube-reserved", "A set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=500Mi) pairs that describe resources reserved for kubernetes system components. Currently only cpu and memory are supported. See http://kubernetes.io/docs/user-guide/compute-resources for more detail. [default=none]")
+	fs.Var(&c.KubeReserved, "kube-reserved", "A set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=500Mi, storage=1Gi) pairs that describe resources reserved for kubernetes system components. Currently cpu, memory and local storage for root file system are supported. See http://kubernetes.io/docs/user-guide/compute-resources for more detail. [default=none]")
 	fs.StringSliceVar(&c.EnforceNodeAllocatable, "enforce-node-allocatable", c.EnforceNodeAllocatable, "A comma separated list of levels of node allocatable enforcement to be enforced by kubelet. Acceptible options are 'pods', 'system-reserved' & 'kube-reserved'. If the latter two options are specified, '--system-reserved-cgroup' & '--kube-reserved-cgroup' must also be set respectively. See https://github.com/kubernetes/community/blob/master/contributors/design-proposals/node-allocatable.md for more details.")
 	fs.StringVar(&c.SystemReservedCgroup, "system-reserved-cgroup", c.SystemReservedCgroup, "Absolute name of the top level cgroup that is used to manage non-kubernetes components for which compute resources were reserved via '--system-reserved' flag. Ex. '/system-reserved'. [default='']")
 	fs.StringVar(&c.KubeReservedCgroup, "kube-reserved-cgroup", c.KubeReservedCgroup, "Absolute name of the top level cgroup that is used to manage kubernetes components for which compute resources were reserved via '--kube-reserved' flag. Ex. '/kube-reserved'. [default='']")

cmd/kubelet/app/server.go

@@ -914,8 +914,8 @@ func parseResourceList(m componentconfig.ConfigurationMap) (v1.ResourceList, err
 	rl := make(v1.ResourceList)
 	for k, v := range m {
 		switch v1.ResourceName(k) {
-		// Only CPU and memory resources are supported.
-		case v1.ResourceCPU, v1.ResourceMemory:
+		// CPU, memory and local storage resources are supported.
+		case v1.ResourceCPU, v1.ResourceMemory, v1.ResourceStorage:
 			q, err := resource.ParseQuantity(v)
 			if err != nil {
 				return nil, err

pkg/apis/componentconfig/v1alpha1/types.go

@@ -551,7 +551,7 @@ type KubeletConfiguration struct {
 	SystemReserved map[string]string `json:"systemReserved"`
 	// A set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=150G) pairs
 	// that describe resources reserved for kubernetes system components.
-	// Currently only cpu and memory are supported. [default=none]
+	// Currently cpu, memory and local storage for root file system are supported. [default=none]
 	// See http://kubernetes.io/docs/user-guide/compute-resources for more detail.
 	KubeReserved map[string]string `json:"kubeReserved"`
 

pkg/kubelet/cadvisor/util.go

@@ -18,6 +18,7 @@ package cadvisor
 
 import (
 	cadvisorapi "github.com/google/cadvisor/info/v1"
+	cadvisorapi2 "github.com/google/cadvisor/info/v2"
 	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/kubernetes/pkg/api/v1"
 )
@@ -33,3 +34,21 @@ func CapacityFromMachineInfo(info *cadvisorapi.MachineInfo) v1.ResourceList {
 	}
 	return c
 }
+
+func StorageScratchCapacityFromFsInfo(info cadvisorapi2.FsInfo) v1.ResourceList {
+	c := v1.ResourceList{
+		v1.ResourceStorage: *resource.NewQuantity(
+			int64(info.Capacity),
+			resource.BinarySI),
+	}
+	return c
+}
+
+func StorageOverlayCapacityFromFsInfo(info cadvisorapi2.FsInfo) v1.ResourceList {
+	c := v1.ResourceList{
+		v1.ResourceStorageOverlay: *resource.NewQuantity(
+			int64(info.Capacity),
+			resource.BinarySI),
+	}
+	return c
+}

pkg/kubelet/cm/node_container_manager.go

@@ -29,6 +29,7 @@ import (
 	"k8s.io/apimachinery/pkg/types"
 	clientv1 "k8s.io/client-go/pkg/api/v1"
 	"k8s.io/kubernetes/pkg/api/v1"
+	"k8s.io/kubernetes/pkg/kubelet/cadvisor"
 	"k8s.io/kubernetes/pkg/kubelet/events"
 	evictionapi "k8s.io/kubernetes/pkg/kubelet/eviction/api"
 )
@@ -180,9 +181,20 @@ func (cm *containerManagerImpl) getNodeAllocatableAbsolute() v1.ResourceList {
 
 }
 
-// GetNodeAllocatable returns amount of compute resource that have to be reserved on this node from scheduling.
+// GetNodeAllocatable returns amount of compute or storage resource that have to be reserved on this node from scheduling.
 func (cm *containerManagerImpl) GetNodeAllocatableReservation() v1.ResourceList {
 	evictionReservation := hardEvictionReservation(cm.HardEvictionThresholds, cm.capacity)
+	if _, ok := cm.capacity[v1.ResourceStorage]; !ok {
+		if cm.cadvisorInterface != nil {
+			if rootfs, err := cm.cadvisorInterface.RootFsInfo(); err == nil {
+				for rName, rCap := range cadvisor.StorageScratchCapacityFromFsInfo(rootfs) {
+					cm.capacity[rName] = rCap
+				}
+			} else {
+				glog.Warning("Error getting rootfs info: %v", err)
+			}
+		}
+	}
 	result := make(v1.ResourceList)
 	for k := range cm.capacity {
 		value := resource.NewQuantity(0, resource.DecimalSI)

pkg/kubelet/eviction/api/types.go

@@ -38,6 +38,8 @@ const (
 	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"
+	// SignalAllocatableNodeFsAvailable is amount of local storage available for pod allocation
+	SignalAllocatableNodeFsAvailable Signal = "allocatableNodeFs.available"
 )
 
 // ThresholdOperator is the operator used to express a Threshold.

pkg/kubelet/eviction/eviction_manager.go

@@ -82,6 +82,8 @@ type managerImpl struct {
 	lastObservations signalObservations
 	// notifiersInitialized indicates if the threshold notifiers have been initialized (i.e. synchronize() has been called once)
 	notifiersInitialized bool
+	// dedicatedImageFs indicates if imagefs is on a separate device from the rootfs
+	dedicatedImageFs *bool
 }
 
 // ensure it implements the required interface
@@ -106,6 +108,7 @@ func NewManager(
 		nodeRef:         nodeRef,
 		nodeConditionsLastObservedAt: nodeConditionsObservedAt{},
 		thresholdsFirstObservedAt:    thresholdsObservedAt{},
+		dedicatedImageFs:             nil,
 	}
 	return manager, manager
 }
@@ -211,21 +214,22 @@ func (m *managerImpl) synchronize(diskInfoProvider DiskInfoProvider, podFunc Act
 	}
 
 	glog.V(3).Infof("eviction manager: synchronize housekeeping")
-
 	// build the ranking functions (if not yet known)
 	// TODO: have a function in cadvisor that lets us know if global housekeeping has completed
-	if len(m.resourceToRankFunc) == 0 || len(m.resourceToNodeReclaimFuncs) == 0 {
-		// this may error if cadvisor has yet to complete housekeeping, so we will just try again in next pass.
-		hasDedicatedImageFs, err := diskInfoProvider.HasDedicatedImageFs()
-		if err != nil {
+	if m.dedicatedImageFs == nil {
+		hasImageFs, ok := diskInfoProvider.HasDedicatedImageFs()
+		if ok != nil {
 			return nil
 		}
-		m.resourceToRankFunc = buildResourceToRankFunc(hasDedicatedImageFs)
-		m.resourceToNodeReclaimFuncs = buildResourceToNodeReclaimFuncs(m.imageGC, hasDedicatedImageFs)
+		m.dedicatedImageFs = &hasImageFs
+		m.resourceToRankFunc = buildResourceToRankFunc(hasImageFs)
+		m.resourceToNodeReclaimFuncs = buildResourceToNodeReclaimFuncs(m.imageGC, hasImageFs)
+
 	}
 
+	activePods := podFunc()
 	// make observations and get a function to derive pod usage stats relative to those observations.
-	observations, statsFunc, err := makeSignalObservations(m.summaryProvider, nodeProvider)
+	observations, statsFunc, err := makeSignalObservations(m.summaryProvider, nodeProvider, activePods, *m.dedicatedImageFs)
 	if err != nil {
 		glog.Errorf("eviction manager: unexpected err: %v", err)
 		return nil
@@ -336,7 +340,11 @@ func (m *managerImpl) synchronize(diskInfoProvider DiskInfoProvider, podFunc Act
 	}
 
 	// the only candidates viable for eviction are those pods that had anything running.
-	activePods := podFunc()
+	if len(activePods) == 0 {
+		glog.Errorf("eviction manager: eviction thresholds have been met, but no pods are active to evict")
+		return nil
+	}
+
 	// rank the running pods for eviction for the specified resource
 	rank(activePods, statsFunc)
 

pkg/kubelet/eviction/helpers.go

@@ -54,6 +54,8 @@ const (
 	resourceNodeFs v1.ResourceName = "nodefs"
 	// nodefs inodes, number.  internal to this module, used to account for local node root filesystem inodes.
 	resourceNodeFsInodes v1.ResourceName = "nodefsInodes"
+	// container overlay storage, in bytes.  internal to this module, used to account for local disk usage for container overlay.
+	resourceOverlay v1.ResourceName = "overlay"
 )
 
 var (
@@ -74,19 +76,25 @@ func init() {
 	signalToNodeCondition[evictionapi.SignalNodeFsAvailable] = v1.NodeDiskPressure
 	signalToNodeCondition[evictionapi.SignalImageFsInodesFree] = v1.NodeDiskPressure
 	signalToNodeCondition[evictionapi.SignalNodeFsInodesFree] = v1.NodeDiskPressure
+	signalToNodeCondition[evictionapi.SignalAllocatableNodeFsAvailable] = v1.NodeDiskPressure
 
 	// map signals to resources (and vice-versa)
 	signalToResource = map[evictionapi.Signal]v1.ResourceName{}
 	signalToResource[evictionapi.SignalMemoryAvailable] = v1.ResourceMemory
 	signalToResource[evictionapi.SignalAllocatableMemoryAvailable] = v1.ResourceMemory
+	signalToResource[evictionapi.SignalAllocatableNodeFsAvailable] = resourceNodeFs
 	signalToResource[evictionapi.SignalImageFsAvailable] = resourceImageFs
 	signalToResource[evictionapi.SignalImageFsInodesFree] = resourceImageFsInodes
 	signalToResource[evictionapi.SignalNodeFsAvailable] = resourceNodeFs
 	signalToResource[evictionapi.SignalNodeFsInodesFree] = resourceNodeFsInodes
+
 	resourceToSignal = map[v1.ResourceName]evictionapi.Signal{}
 	for key, value := range signalToResource {
 		resourceToSignal[value] = key
 	}
+	// Hard-code here to make sure resourceNodeFs maps to evictionapi.SignalNodeFsAvailable
+	// (TODO) resourceToSignal is a map from resource name to a list of signals
+	resourceToSignal[resourceNodeFs] = evictionapi.SignalNodeFsAvailable
 }
 
 // validSignal returns true if the signal is supported.
@@ -234,6 +242,16 @@ func getAllocatableThreshold(allocatableConfig []string) []evictionapi.Threshold
 						Quantity: resource.NewQuantity(int64(0), resource.BinarySI),
 					},
 				},
+				{
+					Signal:   evictionapi.SignalAllocatableNodeFsAvailable,
+					Operator: evictionapi.OpLessThan,
+					Value: evictionapi.ThresholdValue{
+						Quantity: resource.NewQuantity(int64(0), resource.BinarySI),
+					},
+					MinReclaim: &evictionapi.ThresholdValue{
+						Quantity: resource.NewQuantity(int64(0), resource.BinarySI),
+					},
+				},
 			}
 		}
 	}
@@ -382,10 +400,12 @@ func localVolumeNames(pod *v1.Pod) []string {
 func podDiskUsage(podStats statsapi.PodStats, pod *v1.Pod, statsToMeasure []fsStatsType) (v1.ResourceList, error) {
 	disk := resource.Quantity{Format: resource.BinarySI}
 	inodes := resource.Quantity{Format: resource.BinarySI}
+	overlay := resource.Quantity{Format: resource.BinarySI}
 	for _, container := range podStats.Containers {
 		if hasFsStatsType(statsToMeasure, fsStatsRoot) {
 			disk.Add(*diskUsage(container.Rootfs))
 			inodes.Add(*inodeUsage(container.Rootfs))
+			overlay.Add(*diskUsage(container.Rootfs))
 		}
 		if hasFsStatsType(statsToMeasure, fsStatsLogs) {
 			disk.Add(*diskUsage(container.Logs))
@@ -405,8 +425,9 @@ func podDiskUsage(podStats statsapi.PodStats, pod *v1.Pod, statsToMeasure []fsSt
 		}
 	}
 	return v1.ResourceList{
-		resourceDisk:   disk,
-		resourceInodes: inodes,
+		resourceDisk:    disk,
+		resourceInodes:  inodes,
+		resourceOverlay: overlay,
 	}, nil
 }
 
@@ -637,7 +658,7 @@ func (a byEvictionPriority) Less(i, j int) bool {
 }
 
 // makeSignalObservations derives observations using the specified summary provider.
-func makeSignalObservations(summaryProvider stats.SummaryProvider, nodeProvider NodeProvider) (signalObservations, statsFunc, error) {
+func makeSignalObservations(summaryProvider stats.SummaryProvider, nodeProvider NodeProvider, pods []*v1.Pod, withImageFs bool) (signalObservations, statsFunc, error) {
 	summary, err := summaryProvider.Get()
 	if err != nil {
 		return nil, nil, err
@@ -706,6 +727,37 @@ func makeSignalObservations(summaryProvider stats.SummaryProvider, nodeProvider
 			capacity:  memoryAllocatableCapacity.Copy(),
 		}
 	}
+
+	if storageScratchAllocatableCapacity, ok := node.Status.Allocatable[v1.ResourceStorage]; ok {
+		storageScratchAllocatable := storageScratchAllocatableCapacity.Copy()
+		for _, pod := range pods {
+			podStat, ok := statsFunc(pod)
+			if !ok {
+				continue
+			}
+
+			usage, err := podDiskUsage(podStat, pod, []fsStatsType{fsStatsLogs, fsStatsLocalVolumeSource, fsStatsRoot})
+			if err != nil {
+				glog.Warningf("eviction manager: error getting pod disk usage %v", err)
+				continue
+			}
+			// If there is a seperate imagefs set up for container runtimes, the scratch disk usage from nodefs should exclude the overlay usage
+			if withImageFs {
+				diskUsage := usage[resourceDisk]
+				diskUsageP := &diskUsage
+				diskUsagep := diskUsageP.Copy()
+				diskUsagep.Sub(usage[resourceOverlay])
+				storageScratchAllocatable.Sub(*diskUsagep)
+			} else {
+				storageScratchAllocatable.Sub(usage[resourceDisk])
+			}
+		}
+		result[evictionapi.SignalAllocatableNodeFsAvailable] = signalObservation{
+			available: storageScratchAllocatable,
+			capacity:  storageScratchAllocatableCapacity.Copy(),
+		}
+	}
+
 	return result, statsFunc, nil
 }
 

pkg/kubelet/eviction/helpers_test.go

@@ -76,6 +76,16 @@ func TestParseThresholdConfig(t *testing.T) {
 						Quantity: quantityMustParse("0"),
 					},
 				},
+				{
+					Signal:   evictionapi.SignalAllocatableNodeFsAvailable,
+					Operator: evictionapi.OpLessThan,
+					Value: evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("0"),
+					},
+					MinReclaim: &evictionapi.ThresholdValue{
+						Quantity: quantityMustParse("0"),
+					},
+				},
 				{
 					Signal:   evictionapi.SignalMemoryAvailable,
 					Operator: evictionapi.OpLessThan,
@@ -777,8 +787,7 @@ func TestMakeSignalObservations(t *testing.T) {
 	if res.CmpInt64(int64(allocatableMemoryCapacity)) != 0 {
 		t.Errorf("Expected Threshold %v to be equal to value %v", res.Value(), allocatableMemoryCapacity)
 	}
-	actualObservations, statsFunc, err := makeSignalObservations(provider, nodeProvider)
-
+	actualObservations, statsFunc, err := makeSignalObservations(provider, nodeProvider, pods, false)
 	if err != nil {
 		t.Errorf("Unexpected err: %v", err)
 	}

pkg/kubelet/kubelet.go

@@ -37,6 +37,7 @@ import (
 	clientgoclientset "k8s.io/client-go/kubernetes"
 
 	cadvisorapi "github.com/google/cadvisor/info/v1"
+	cadvisorapiv2 "github.com/google/cadvisor/info/v2"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/fields"
 	"k8s.io/apimachinery/pkg/labels"
@@ -927,6 +928,9 @@ type Kubelet struct {
 	// Cached MachineInfo returned by cadvisor.
 	machineInfo *cadvisorapi.MachineInfo
 
+	//Cached RootFsInfo returned by cadvisor
+	rootfsInfo *cadvisorapiv2.FsInfo
+
 	// Handles certificate rotations.
 	serverCertificateManager certificate.Manager
 

pkg/kubelet/kubelet_cadvisor.go

@@ -100,3 +100,15 @@ func (kl *Kubelet) GetCachedMachineInfo() (*cadvisorapi.MachineInfo, error) {
 	}
 	return kl.machineInfo, nil
 }
+
+// GetCachedRootFsInfo assumes that the rootfs info can't change without a reboot
+func (kl *Kubelet) GetCachedRootFsInfo() (cadvisorapiv2.FsInfo, error) {
+	if kl.rootfsInfo == nil {
+		info, err := kl.cadvisor.RootFsInfo()
+		if err != nil {
+			return cadvisorapiv2.FsInfo{}, err
+		}
+		kl.rootfsInfo = &info
+	}
+	return *kl.rootfsInfo, nil
+}

pkg/kubelet/kubelet_node_status.go

@@ -551,6 +551,26 @@ func (kl *Kubelet) setNodeStatusMachineInfo(node *v1.Node) {
 		node.Status.NodeInfo.BootID = info.BootID
 	}
 
+	rootfs, err := kl.GetCachedRootFsInfo()
+	if err != nil {
+		node.Status.Capacity[v1.ResourceStorage] = resource.MustParse("0Gi")
+	} else {
+		for rName, rCap := range cadvisor.StorageScratchCapacityFromFsInfo(rootfs) {
+			node.Status.Capacity[rName] = rCap
+		}
+	}
+
+	if hasDedicatedImageFs, _ := kl.HasDedicatedImageFs(); hasDedicatedImageFs {
+		imagesfs, err := kl.ImagesFsInfo()
+		if err != nil {
+			node.Status.Capacity[v1.ResourceStorageOverlay] = resource.MustParse("0Gi")
+		} else {
+			for rName, rCap := range cadvisor.StorageOverlayCapacityFromFsInfo(imagesfs) {
+				node.Status.Capacity[rName] = rCap
+			}
+		}
+	}
+
 	// Set Allocatable.
 	if node.Status.Allocatable == nil {
 		node.Status.Allocatable = make(v1.ResourceList)