【kubernetes/k8s源码分析】kubelet源码分析之资源上报

Dear 丶 2022-05-08 15:44 267阅读 0赞

# 0. 数据流 #

路径： pkg/kubelet/kubelet.go

Run函数（） ->

syncNodeStatus ()  ->

registerWithAPIServer() ->

initialNode() ->

setNodeStatus ->

调用的setNodeStatusFuncs函数列表

# 1. NewMainKubelet函数 #

注册函数defaultNodeStatusFuncs

// Generating the status funcs should be the last thing we do,
    	// since this relies on the rest of the Kubelet having been constructed.
    	klet.setNodeStatusFuncs = klet.defaultNodeStatusFuncs()

# 2. defaultNodeStatusFuncs函数 #

添加了一大堆函数（func(\*v1.node) error）列表

// defaultNodeStatusFuncs is a factory that generates the default set of
    // setNodeStatus funcs
    func (kl *Kubelet) defaultNodeStatusFuncs() []func(*v1.Node) error {
    	// if cloud is not nil, we expect the cloud resource sync manager to exist
    	var nodeAddressesFunc func() ([]v1.NodeAddress, error)
    	if kl.cloud != nil {
    		nodeAddressesFunc = kl.cloudResourceSyncManager.NodeAddresses
    	}
    	var validateHostFunc func() error
    	if kl.appArmorValidator != nil {
    		validateHostFunc = kl.appArmorValidator.ValidateHost
    	}
    	var setters []func(n *v1.Node) error
    	setters = append(setters,
    		nodestatus.NodeAddress(kl.nodeIP, kl.nodeIPValidator, kl.hostname, kl.hostnameOverridden, kl.externalCloudProvider, kl.cloud, nodeAddressesFunc),
    		nodestatus.MachineInfo(string(kl.nodeName), kl.maxPods, kl.podsPerCore, kl.GetCachedMachineInfo, kl.containerManager.GetCapacity,
    			kl.containerManager.GetDevicePluginResourceCapacity, kl.containerManager.GetNodeAllocatableReservation, kl.recordEvent),
    		nodestatus.VersionInfo(kl.cadvisor.VersionInfo, kl.containerRuntime.Type, kl.containerRuntime.Version),
    		nodestatus.DaemonEndpoints(kl.daemonEndpoints),
    		nodestatus.Images(kl.nodeStatusMaxImages, kl.imageManager.GetImageList),
    		nodestatus.GoRuntime(),
    	)
    	if utilfeature.DefaultFeatureGate.Enabled(features.AttachVolumeLimit) {
    		setters = append(setters, nodestatus.VolumeLimits(kl.volumePluginMgr.ListVolumePluginWithLimits))
    	}
    	setters = append(setters,
    		nodestatus.OutOfDiskCondition(kl.clock.Now, kl.recordNodeStatusEvent),
    		nodestatus.MemoryPressureCondition(kl.clock.Now, kl.evictionManager.IsUnderMemoryPressure, kl.recordNodeStatusEvent),
    		nodestatus.DiskPressureCondition(kl.clock.Now, kl.evictionManager.IsUnderDiskPressure, kl.recordNodeStatusEvent),
    		nodestatus.PIDPressureCondition(kl.clock.Now, kl.evictionManager.IsUnderPIDPressure, kl.recordNodeStatusEvent),
    		nodestatus.ReadyCondition(kl.clock.Now, kl.runtimeState.runtimeErrors, kl.runtimeState.networkErrors, validateHostFunc, kl.containerManager.Status, kl.recordNodeStatusEvent),
    		nodestatus.VolumesInUse(kl.volumeManager.ReconcilerStatesHasBeenSynced, kl.volumeManager.GetVolumesInUse),
    		// TODO(mtaufen): I decided not to move this setter for now, since all it does is send an event
    		// and record state back to the Kubelet runtime object. In the future, I'd like to isolate
    		// these side-effects by decoupling the decisions to send events and partial status recording
    		// from the Node setters.
    		kl.recordNodeSchedulableEvent,
    	)
    	return setters
    }

# 3. NodeAddress函数 #

node.Status.Addresses = []v1.NodeAddress{
    				{Type: v1.NodeInternalIP, Address: ipAddr.String()},
    				{Type: v1.NodeHostName, Address: hostname},
    			}

# 例如 #

status:
      addresses:
      - address: 10.12.51.209
        type: InternalIP
      - address: 10.12.51.209
        type: Hostname

# 4. DiskPressureCondition函数 #

主要是调用pressureFunc函数（IsUnderDiskPressure），主要匹配DiskPressure

func DiskPressureCondition(nowFunc func() time.Time, // typically Kubelet.clock.Now
    	pressureFunc func() bool, // typically Kubelet.evictionManager.IsUnderDiskPressure
    	recordEventFunc func(eventType, event string), // typically Kubelet.recordNodeStatusEvent
    ) Setter {
    	return func(node *v1.Node) error {
    		currentTime := metav1.NewTime(nowFunc())
    		var condition *v1.NodeCondition
    
    		// Check if NodeDiskPressure condition already exists and if it does, just pick it up for update.
    		for i := range node.Status.Conditions {
    			if node.Status.Conditions[i].Type == v1.NodeDiskPressure {
    				condition = &node.Status.Conditions[i]
    			}
    		}
    
    		newCondition := false
    		// If the NodeDiskPressure condition doesn't exist, create one
    		if condition == nil {
    			condition = &v1.NodeCondition{
    				Type:   v1.NodeDiskPressure,
    				Status: v1.ConditionUnknown,
    			}
    			// cannot be appended to node.Status.Conditions here because it gets
    			// copied to the slice. So if we append to the slice here none of the
    			// updates we make below are reflected in the slice.
    			newCondition = true
    		}
    
    		// Update the heartbeat time
    		condition.LastHeartbeatTime = currentTime
    
    		// Note: The conditions below take care of the case when a new NodeDiskPressure condition is
    		// created and as well as the case when the condition already exists. When a new condition
    		// is created its status is set to v1.ConditionUnknown which matches either
    		// condition.Status != v1.ConditionTrue or
    		// condition.Status != v1.ConditionFalse in the conditions below depending on whether
    		// the kubelet is under disk pressure or not.
    		if pressureFunc() {
    			if condition.Status != v1.ConditionTrue {
    				condition.Status = v1.ConditionTrue
    				condition.Reason = "KubeletHasDiskPressure"
    				condition.Message = "kubelet has disk pressure"
    				condition.LastTransitionTime = currentTime
    				recordEventFunc(v1.EventTypeNormal, "NodeHasDiskPressure")
    			}
    		} else if condition.Status != v1.ConditionFalse {
    			condition.Status = v1.ConditionFalse
    			condition.Reason = "KubeletHasNoDiskPressure"
    			condition.Message = "kubelet has no disk pressure"
    			condition.LastTransitionTime = currentTime
    			recordEventFunc(v1.EventTypeNormal, "NodeHasNoDiskPressure")
    		}
    
    		if newCondition {
    			node.Status.Conditions = append(node.Status.Conditions, *condition)
    		}
    		return nil
    	}
    }

例如：

conditions:
      - lastHeartbeatTime: 2018-10-16T02:10:03Z
        lastTransitionTime: 2018-08-29T03:03:57Z
        message: kubelet has sufficient disk space available
        reason: KubeletHasSufficientDisk
        status: "False"
        type: OutOfDisk
      - lastHeartbeatTime: 2018-10-16T02:10:03Z
        lastTransitionTime: 2018-10-15T10:32:09Z
        message: kubelet has sufficient memory available
        reason: KubeletHasSufficientMemory
        status: "False"
        type: MemoryPressure
      - lastHeartbeatTime: 2018-10-16T02:10:03Z
        lastTransitionTime: 2018-10-15T19:40:44Z
        message: kubelet has no disk pressure
        reason: KubeletHasNoDiskPressure
        status: "False"
        type: DiskPressure
      - lastHeartbeatTime: 2018-10-16T02:10:03Z
        lastTransitionTime: 2018-10-15T10:32:09Z
        message: kubelet is posting ready status
        reason: KubeletReady
        status: "True"
        type: Ready