Kubernetes 调度器实现原理

// pkg/scheduler/framework/plugins/registry.go

// NewInTreeRegistry 使用所有内部插件构建注册表。
// 外部插件可以通过 WithFrameworkOutOfTreeRegistry 选项注册额外的插件。
func NewInTreeRegistry() runtime.Registry {
 fts := plfeature.Features{
  EnableDynamicResourceAllocation:              feature.DefaultFeatureGate.Enabled(features.DynamicResourceAllocation),
  EnableReadWriteOncePod:                       feature.DefaultFeatureGate.Enabled(features.ReadWriteOncePod),
  EnableVolumeCapacityPriority:                 feature.DefaultFeatureGate.Enabled(features.VolumeCapacityPriority),
  EnableMinDomainsInPodTopologySpread:          feature.DefaultFeatureGate.Enabled(features.MinDomainsInPodTopologySpread),
  EnableNodeInclusionPolicyInPodTopologySpread: feature.DefaultFeatureGate.Enabled(features.NodeInclusionPolicyInPodTopologySpread),
  EnableMatchLabelKeysInPodTopologySpread:      feature.DefaultFeatureGate.Enabled(features.MatchLabelKeysInPodTopologySpread),
  EnablePodSchedulingReadiness:                 feature.DefaultFeatureGate.Enabled(features.PodSchedulingReadiness),
 }

 registry := runtime.Registry{
  dynamicresources.Name:                runtime.FactoryAdapter(fts, dynamicresources.New),
  selectorspread.Name:                  selectorspread.New,
  imagelocality.Name:                   imagelocality.New,
  tainttoleration.Name:                 tainttoleration.New,
  nodename.Name:                        nodename.New,
  nodeports.Name:                       nodeports.New,
  nodeaffinity.Name:                    nodeaffinity.New,
  podtopologyspread.Name:               runtime.FactoryAdapter(fts, podtopologyspread.New),
  nodeunschedulable.Name:               nodeunschedulable.New,
  noderesources.Name:                   runtime.FactoryAdapter(fts, noderesources.NewFit),
  noderesources.BalancedAllocationName: runtime.FactoryAdapter(fts, noderesources.NewBalancedAllocation),
  volumebinding.Name:                   runtime.FactoryAdapter(fts, volumebinding.New),
  volumerestrictions.Name:              runtime.FactoryAdapter(fts, volumerestrictions.New),
  volumezone.Name:                      volumezone.New,
  nodevolumelimits.CSIName:             runtime.FactoryAdapter(fts, nodevolumelimits.NewCSI),
  nodevolumelimits.EBSName:             runtime.FactoryAdapter(fts, nodevolumelimits.NewEBS),
  nodevolumelimits.GCEPDName:           runtime.FactoryAdapter(fts, nodevolumelimits.NewGCEPD),
  nodevolumelimits.AzureDiskName:       runtime.FactoryAdapter(fts, nodevolumelimits.NewAzureDisk),
  nodevolumelimits.CinderName:          runtime.FactoryAdapter(fts, nodevolumelimits.NewCinder),
  interpodaffinity.Name:                interpodaffinity.New,
  queuesort.Name:                       queuesort.New,
  defaultbinder.Name:                   defaultbinder.New,
  defaultpreemption.Name:               runtime.FactoryAdapter(fts, defaultpreemption.New),
  schedulinggates.Name:                 runtime.FactoryAdapter(fts, schedulinggates.New),
 }

 return registry
}

// Plugin is the parent type for all the scheduling framework plugins.
type Plugin interface {
 Name() string
}

// PreEnqueuePlugin is an interface that must be implemented by "PreEnqueue" plugins.
// These plugins are called prior to adding Pods to activeQ.
// Note: an preEnqueue plugin is expected to be lightweight and efficient, so it's not expected to
// involve expensive calls like accessing external endpoints; otherwise it'd block other
// Pods' enqueuing in event handlers.
type PreEnqueuePlugin interface {
 Plugin
 // PreEnqueue is called prior to adding Pods to activeQ.
 PreEnqueue(ctx context.Context, p *v1.Pod) *Status
}

// LessFunc is the function to sort pod info
type LessFunc func(podInfo1, podInfo2 *QueuedPodInfo) bool

// QueueSortPlugin is an interface that must be implemented by "QueueSort" plugins.
// These plugins are used to sort pods in the scheduling queue. Only one queue sort
// plugin may be enabled at a time.
type QueueSortPlugin interface {
 Plugin
 // Less are used to sort pods in the scheduling queue.
 Less(*QueuedPodInfo, *QueuedPodInfo) bool
}

// EnqueueExtensions is an optional interface that plugins can implement to efficiently
// move unschedulable Pods in internal scheduling queues. Plugins
// that fail pod scheduling (e.g., Filter plugins) are expected to implement this interface.
type EnqueueExtensions interface {
 // EventsToRegister returns a series of possible events that may cause a Pod
 // failed by this plugin schedulable.
 // The events will be registered when instantiating the internal scheduling queue,
 // and leveraged to build event handlers dynamically.
 // Note: the returned list needs to be static (not depend on configuration parameters);
 // otherwise it would lead to undefined behavior.
 EventsToRegister() []ClusterEvent
}

// PreFilterExtensions is an interface that is included in plugins that allow specifying
// callbacks to make incremental updates to its supposedly pre-calculated
// state.
type PreFilterExtensions interface {
 // AddPod is called by the framework while trying to evaluate the impact
 // of adding podToAdd to the node while scheduling podToSchedule.
 AddPod(ctx context.Context, state *CycleState, podToSchedule *v1.Pod, podInfoToAdd *PodInfo, nodeInfo *NodeInfo) *Status
 // RemovePod is called by the framework while trying to evaluate the impact
 // of removing podToRemove from the node while scheduling podToSchedule.
 RemovePod(ctx context.Context, state *CycleState, podToSchedule *v1.Pod, podInfoToRemove *PodInfo, nodeInfo *NodeInfo) *Status
}

// PreFilterPlugin is an interface that must be implemented by "PreFilter" plugins.
// These plugins are called at the beginning of the scheduling cycle.
type PreFilterPlugin interface {
 Plugin
 // PreFilter is called at the beginning of the scheduling cycle. All PreFilter
 // plugins must return success or the pod will be rejected. PreFilter could optionally
 // return a PreFilterResult to influence which nodes to evaluate downstream. This is useful
 // for cases where it is possible to determine the subset of nodes to process in O(1) time.
 PreFilter(ctx context.Context, state *CycleState, p *v1.Pod) (*PreFilterResult, *Status)
 // PreFilterExtensions returns a PreFilterExtensions interface if the plugin implements one,
 // or nil if it does not. A Pre-filter plugin can provide extensions to incrementally
 // modify its pre-processed info. The framework guarantees that the extensions
 // AddPod/RemovePod will only be called after PreFilter, possibly on a cloned
 // CycleState, and may call those functions more than once before calling
 // Filter again on a specific node.
 PreFilterExtensions() PreFilterExtensions
}

// FilterPlugin is an interface for Filter plugins. These plugins are called at the
// filter extension point for filtering out hosts that cannot run a pod.
// This concept used to be called 'predicate' in the original scheduler.
// These plugins should return "Success", "Unschedulable" or "Error" in Status.code.
// However, the scheduler accepts other valid codes as well.
// Anything other than "Success" will lead to exclusion of the given host from
// running the pod.
type FilterPlugin interface {
 Plugin
 // Filter is called by the scheduling framework.
 // All FilterPlugins should return "Success" to declare that
 // the given node fits the pod. If Filter doesn't return "Success",
 // it will return "Unschedulable", "UnschedulableAndUnresolvable" or "Error".
 // For the node being evaluated, Filter plugins should look at the passed
 // nodeInfo reference for this particular node's information (e.g., pods
 // considered to be running on the node) instead of looking it up in the
 // NodeInfoSnapshot because we don't guarantee that they will be the same.
 // For example, during preemption, we may pass a copy of the original
 // nodeInfo object that has some pods removed from it to evaluate the
 // possibility of preempting them to schedule the target pod.
 Filter(ctx context.Context, state *CycleState, pod *v1.Pod, nodeInfo *NodeInfo) *Status
}

// PostFilterPlugin is an interface for "PostFilter" plugins. These plugins are called
// after a pod cannot be scheduled.
type PostFilterPlugin interface {
 Plugin
 // PostFilter is called by the scheduling framework.
 // A PostFilter plugin should return one of the following statuses:
 // - Unschedulable: the plugin gets executed successfully but the pod cannot be made schedulable.
 // - Success: the plugin gets executed successfully and the pod can be made schedulable.
 // - Error: the plugin aborts due to some internal error.
 //
 // Informational plugins should be configured ahead of other ones, and always return Unschedulable status.
 // Optionally, a non-nil PostFilterResult may be returned along with a Success status. For example,
 // a preemption plugin may choose to return nominatedNodeName, so that framework can reuse that to update the
 // preemptor pod's .spec.status.nominatedNodeName field.
 PostFilter(ctx context.Context, state *CycleState, pod *v1.Pod, filteredNodeStatusMap NodeToStatusMap) (*PostFilterResult, *Status)
}

// PreScorePlugin is an interface for "PreScore" plugin. PreScore is an
// informational extension point. Plugins will be called with a list of nodes
// that passed the filtering phase. A plugin may use this data to update internal
// state or to generate logs/metrics.
type PreScorePlugin interface {
 Plugin
 // PreScore is called by the scheduling framework after a list of nodes
 // passed the filtering phase. All prescore plugins must return success or
 // the pod will be rejected
 PreScore(ctx context.Context, state *CycleState, pod *v1.Pod, nodes []*v1.Node) *Status
}

// ScoreExtensions is an interface for Score extended functionality.
type ScoreExtensions interface {
 // NormalizeScore is called for all node scores produced by the same plugin's "Score"
 // method. A successful run of NormalizeScore will update the scores list and return
 // a success status.
 NormalizeScore(ctx context.Context, state *CycleState, p *v1.Pod, scores NodeScoreList) *Status
}

// ScorePlugin is an interface that must be implemented by "Score" plugins to rank
// nodes that passed the filtering phase.
type ScorePlugin interface {
 Plugin
 // Score is called on each filtered node. It must return success and an integer
 // indicating the rank of the node. All scoring plugins must return success or
 // the pod will be rejected.
 Score(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string) (int64, *Status)

 // ScoreExtensions returns a ScoreExtensions interface if it implements one, or nil if does not.
 ScoreExtensions() ScoreExtensions
}

// ReservePlugin is an interface for plugins with Reserve and Unreserve
// methods. These are meant to update the state of the plugin. This concept
// used to be called 'assume' in the original scheduler. These plugins should
// return only Success or Error in Status.code. However, the scheduler accepts
// other valid codes as well. Anything other than Success will lead to
// rejection of the pod.
type ReservePlugin interface {
 Plugin
 // Reserve is called by the scheduling framework when the scheduler cache is
 // updated. If this method returns a failed Status, the scheduler will call
 // the Unreserve method for all enabled ReservePlugins.
 Reserve(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string) *Status
 // Unreserve is called by the scheduling framework when a reserved pod was
 // rejected, an error occurred during reservation of subsequent plugins, or
 // in a later phase. The Unreserve method implementation must be idempotent
 // and may be called by the scheduler even if the corresponding Reserve
 // method for the same plugin was not called.
 Unreserve(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string)
}

// PreBindPlugin is an interface that must be implemented by "PreBind" plugins.
// These plugins are called before a pod being scheduled.
type PreBindPlugin interface {
 Plugin
 // PreBind is called before binding a pod. All prebind plugins must return
 // success or the pod will be rejected and won't be sent for binding.
 PreBind(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string) *Status
}

// PostBindPlugin is an interface that must be implemented by "PostBind" plugins.
// These plugins are called after a pod is successfully bound to a node.
type PostBindPlugin interface {
 Plugin
 // PostBind is called after a pod is successfully bound. These plugins are
 // informational. A common application of this extension point is for cleaning
 // up. If a plugin needs to clean-up its state after a pod is scheduled and
 // bound, PostBind is the extension point that it should register.
 PostBind(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string)
}

// PermitPlugin is an interface that must be implemented by "Permit" plugins.
// These plugins are called before a pod is bound to a node.
type PermitPlugin interface {
 Plugin
 // Permit is called before binding a pod (and before prebind plugins). Permit
 // plugins are used to prevent or delay the binding of a Pod. A permit plugin
 // must return success or wait with timeout duration, or the pod will be rejected.
 // The pod will also be rejected if the wait timeout or the pod is rejected while
 // waiting. Note that if the plugin returns "wait", the framework will wait only
 // after running the remaining plugins given that no other plugin rejects the pod.
 Permit(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string) (*Status, time.Duration)
}

// BindPlugin is an interface that must be implemented by "Bind" plugins. Bind
// plugins are used to bind a pod to a Node.
type BindPlugin interface {
 Plugin
 // Bind plugins will not be called until all pre-bind plugins have completed. Each
 // bind plugin is called in the configured order. A bind plugin may choose whether
 // or not to handle the given Pod. If a bind plugin chooses to handle a Pod, the
 // remaining bind plugins are skipped. When a bind plugin does not handle a pod,
 // it must return Skip in its Status code. If a bind plugin returns an Error, the
 // pod is rejected and will not be bound.
 Bind(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string) *Status
}

apiVersion: kubescheduler.config.k8s.io/v1
kind: KubeSchedulerConfiguration

---
plugins:
  reserve:
    enabled:
      - name: foo
      - name: bar
    disabled:
      - name: baz
  preBind:
    enabled:
      - name: foo
    disabled:
      - name: baz

pluginConfig:
  - name: foo
    args: >
      foo插件可以解析的任意内容

apiVersion: kubescheduler.config.k8s.io/v1
kind: KubeSchedulerConfiguration

---
profiles:
  - plugins:
      reserve:
        enabled:
          - name: bar
          - name: foo
        disabled:
          - name: foo

// pkg/scheduler/algorithmprovider/registry.go
func NewRegistry() Registry {
 return Registry{
  // FactoryMap:
  // New plugins are registered here.
  // example:
  // {
  //  stateful_plugin.Name: stateful.NewStatefulMultipointExample,
  //  fooplugin.Name: fooplugin.New,
  // }
 }
}

// Option configures a framework.Registry.
type Option func(framework.Registry) error

// NewSchedulerCommand creates a *cobra.Command object with default parameters and registryOptions
func NewSchedulerCommand(registryOptions ...Option) *cobra.Command {
  ......
}

func WithPlugin(name string, factory runtime.PluginFactory) Option {
 return func(registry runtime.Registry) error {
  return registry.Register(name, factory)
 }
}

package main

import (
 "k8s.io/component-base/cli"
 "k8s.io/kubernetes/cmd/kube-scheduler/app"
 "math/rand"
 "os"
 // Ensure scheme package is initialized.
 _ "simple-scheduler/pkg/scheduler/apis/config/schema"
 "simple-scheduler/pkg/scheduler/framework/plugins"
 "time"
)

func main() {
 rand.Seed(time.Now().UTC().UnixNano())
 command := app.NewSchedulerCommand(
  app.WithPlugin(plugins.Name, plugins.New))
 code := cli.Run(command)
 os.Exit(code)
}

type PluginFactory = func(configuration runtime.Object, f framework.Handle) (framework.Plugin, error)

package plugins

import (
 "context"
 "fmt"
 v1 "k8s.io/api/core/v1"
 "k8s.io/apimachinery/pkg/runtime"
 "k8s.io/klog/v2"
 "k8s.io/kubernetes/pkg/scheduler/framework"
 "simple-scheduler/pkg/scheduler/apis/config"
 "simple-scheduler/pkg/scheduler/apis/config/validation"
)

const Name = "sample-plugin"

type Sample struct {
 args   *config.SampleArgs
 handle framework.Handle
}

func (s *Sample) Name() string {
 return Name
}

func (s *Sample) PreFilter(ctx context.Context, cycleState *framework.CycleState, pod *v1.Pod) (*framework.PreFilterResult, *framework.Status) {
 klog.V(3).Infof("prefilter pod: %v", pod.Name)
 return nil, nil
}

func (s *Sample) Filter(ctx context.Context, cycleState *framework.CycleState, pod *v1.Pod, nodeInfo *framework.NodeInfo) *framework.Status {
 klog.V(3).Infof("filter pod: %v, node: %v", pod.Name, nodeInfo.Node().Name)
 return framework.NewStatus(framework.Success, "")
}

func (s *Sample) PreBind(ctx context.Context, state *framework.CycleState, pod *v1.Pod, nodeName string) *framework.Status {
 if nodeInfo, err := s.handle.SnapshotSharedLister().NodeInfos().Get(nodeName); err != nil {
  return framework.NewStatus(framework.Error, fmt.Sprintf("prebind get node: %s info error: %s", nodeName, err.Error()))
 } else {
  klog.V(3).Infof("prebind node info: %+v", nodeInfo.Node())
  return framework.NewStatus(framework.Success, "")
 }
}

func New(fpArgs runtime.Object, fh framework.Handle) (framework.Plugin, error) {
 args, ok := fpArgs.(*config.SampleArgs)
 if !ok {
  return nil, fmt.Errorf("got args of type %T, want *SampleArgs", fpArgs)
 }
 if err := validation.ValidateSamplePluginArgs(*args); err != nil {
  return nil, err
 }
 return &Sample{
  args:   args,
  handle: fh,
 }, nil
}

// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

type SampleArgs struct {
 metav1.TypeMeta
 FavoriteColor  string `json:"favorite_color,omitempty"`
 FavoriteNumber int    `json:"favorite_number,omitempty"`
 ThanksTo       string `json:"thanks_to,omitempty"`
}

# sample-scheduler.yaml
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: sample-scheduler-clusterrole
rules:
  - apiGroups:
      - ""
    resources:
      - endpoints
      - events
    verbs:
      - create
      - get
      - update
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - pods
    verbs:
      - delete
      - get
      - list
      - watch
      - update
  - apiGroups:
      - ""
    resources:
      - bindings
      - pods/binding
    verbs:
      - create
  - apiGroups:
      - ""
    resources:
      - pods/status
    verbs:
      - patch
      - update
  - apiGroups:
      - ""
    resources:
      - replicationcontrollers
      - services
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - apps
      - extensions
    resources:
      - replicasets
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - apps
    resources:
      - statefulsets
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - policy
    resources:
      - poddisruptionbudgets
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - persistentvolumeclaims
      - persistentvolumes
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - configmaps
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - "storage.k8s.io"
    resources:
      - storageclasses
      - csinodes
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - "coordination.k8s.io"
    resources:
      - leases
    verbs:
      - create
      - get
      - list
      - update
  - apiGroups:
      - "events.k8s.io"
    resources:
      - events
    verbs:
      - create
      - patch
      - update
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: sample-scheduler-sa
  namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: sample-scheduler-clusterrolebinding
  namespace: kube-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: sample-scheduler-clusterrole
subjects:
  - kind: ServiceAccount
    name: sample-scheduler-sa
    namespace: kube-system
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: scheduler-config
  namespace: kube-system
data:
  scheduler-config.yaml: |
    apiVersion: kubescheduler.config.k8s.io/v1
    kind: KubeSchedulerConfiguration
    leaderElection:
      leaderElect: true
      leaseDuration: 15s
      renewDeadline: 10s
      resourceLock: endpointsleases
      resourceName: sample-scheduler
      resourceNamespace: kube-system
      retryPeriod: 2s
    profiles:
      - schedulerName: sample-scheduler
        plugins:
          preFilter:
            enabled:
              - name: "sample-plugin"
          filter:
            enabled:
              - name: "sample-plugin"
        pluginConfig:
          - name: sample-plugin
            args:  # runtime.Object
              favorColor: "#326CE5"
              favorNumber: 7
              thanksTo: "Kubernetes"
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: sample-scheduler
  namespace: kube-system
  labels:
    component: sample-scheduler
spec:
  selector:
    matchLabels:
      component: sample-scheduler
  template:
    metadata:
      labels:
        component: sample-scheduler
    spec:
      serviceAccountName: sample-scheduler-sa
      priorityClassName: system-cluster-critical
      volumes:
        - name: scheduler-config
          configMap:
            name: scheduler-config
      containers:
        - name: scheduler
          image: cnych/sample-scheduler:v0.26.4
          imagePullPolicy: IfNotPresent
          command:
            - sample-scheduler
            - --cnotallow=/etc/kubernetes/scheduler-config.yaml
            - --v=3
          volumeMounts:
            - name: scheduler-config
              mountPath: /etc/kubernetes

# test-scheduler.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-scheduler
spec:
  selector:
    matchLabels:
      app: test-scheduler
  template:
    metadata:
      labels:
        app: test-scheduler
    spec:
      schedulerName: sample-scheduler # 指定使用的调度器，不指定使用默认的default-scheduler
      containers:
        - image: nginx:1.7.9
          imagePullPolicy: IfNotPresent
          name: nginx
          ports:
            - containerPort: 80

➜ kubectl get pods -n kube-system -l compnotallow=sample-scheduler
NAME                               READY   STATUS    RESTARTS   AGE
sample-scheduler-896658cd7-k7vcl   1/1     Running   0          57s
➜ kubectl logs -f sample-scheduler-896658cd7-k7vcl -n kube-system
I0114 09:14:18.878613       1 eventhandlers.go:173] add event for unscheduled pod default/test-scheduler-6486fd49fc-zjhcx
I0114 09:14:18.878670       1 scheduler.go:464] Attempting to schedule pod: default/test-scheduler-6486fd49fc-zjhcx
I0114 09:14:18.878706       1 sample.go:77] "Start PreFilter Pod" pod="test-scheduler-6486fd49fc-zjhcx"
I0114 09:14:18.878802       1 sample.go:93] "Start Filter Pod" pod="test-scheduler-6486fd49fc-zjhcx" node="node2" preFilterState=&{Resource:{MilliCPU:0 Memory:0 EphemeralStorage:0 AllowedPodNumber:0 ScalarResources:map[]}}
I0114 09:14:18.878835       1 sample.go:93] "Start Filter Pod" pod="test-scheduler-6486fd49fc-zjhcx" node="node1" preFilterState=&{Resource:{MilliCPU:0 Memory:0 EphemeralStorage:0 AllowedPodNumber:0 ScalarResources:map[]}}
I0114 09:14:18.879043       1 default_binder.go:51] Attempting to bind default/test-scheduler-6486fd49fc-zjhcx to node1
I0114 09:14:18.886360       1 scheduler.go:609] "Successfully bound pod to node" pod="default/test-scheduler-6486fd49fc-zjhcx" node="node1" evaluatedNodes=3 feasibleNodes=2
I0114 09:14:18.887426       1 eventhandlers.go:205] delete event for unscheduled pod default/test-scheduler-6486fd49fc-zjhcx
I0114 09:14:18.887475       1 eventhandlers.go:225] add event for scheduled pod default/test-scheduler-6486fd49fc-zjhcx

➜ kubectl get pods
NAME                              READY   STATUS    RESTARTS       AGE
test-scheduler-6486fd49fc-zjhcx   1/1     Running   0              35s
➜ kubectl get pod test-scheduler-6486fd49fc-zjhcx -o yaml
......
restartPolicy: Always
schedulerName: sample-scheduler
securityContext: {}
serviceAccount: default
......