Create a node startup latency tracker

Signed-off-by: Qiutong Song <songqt01@gmail.com>

cmd/kubelet/app/server.go

@@ -833,6 +833,10 @@ func run(ctx context.Context, s *options.KubeletServer, kubeDeps *kubelet.Depend
 		kubeDeps.PodStartupLatencyTracker = kubeletutil.NewPodStartupLatencyTracker()
 	}
 
+	if kubeDeps.NodeStartupLatencyTracker == nil {
+		kubeDeps.NodeStartupLatencyTracker = kubeletutil.NewNodeStartupLatencyTracker()
+	}
+
 	// TODO(vmarmol): Do this through container config.
 	oomAdjuster := kubeDeps.OOMAdjuster
 	if err := oomAdjuster.ApplyOOMScoreAdj(0, int(s.OOMScoreAdj)); err != nil {

pkg/kubelet/kubelet.go

@@ -271,6 +271,7 @@ type Dependencies struct {
 	RemoteRuntimeService      internalapi.RuntimeService
 	RemoteImageService        internalapi.ImageManagerService
 	PodStartupLatencyTracker  util.PodStartupLatencyTracker
+	NodeStartupLatencyTracker util.NodeStartupLatencyTracker
 	// remove it after cadvisor.UsingLegacyCadvisorStats dropped.
 	useLegacyCadvisorStats bool
 }
@@ -552,6 +553,7 @@ func NewMainKubelet(kubeCfg *kubeletconfiginternal.KubeletConfiguration,
 		keepTerminatedPodVolumes:       keepTerminatedPodVolumes,
 		nodeStatusMaxImages:            nodeStatusMaxImages,
 		tracer:                         tracer,
+		nodeStartupLatencyTracker:      kubeDeps.NodeStartupLatencyTracker,
 	}
 
 	if klet.cloud != nil {
@@ -1293,6 +1295,9 @@ type Kubelet struct {
 
 	// OpenTelemetry Tracer
 	tracer trace.Tracer
+
+	// Track node startup latencies
+	nodeStartupLatencyTracker util.NodeStartupLatencyTracker
 }
 
 // ListPodStats is delegated to StatsProvider, which implements stats.Provider interface

pkg/kubelet/kubelet_node_status.go

@@ -52,6 +52,9 @@ func (kl *Kubelet) registerWithAPIServer() {
 	if kl.registrationCompleted {
 		return
 	}
+
+	kl.nodeStartupLatencyTracker.RecordAttemptRegisterNode()
+
 	step := 100 * time.Millisecond
 
 	for {
@@ -85,6 +88,7 @@ func (kl *Kubelet) registerWithAPIServer() {
 func (kl *Kubelet) tryRegisterWithAPIServer(node *v1.Node) bool {
 	_, err := kl.kubeClient.CoreV1().Nodes().Create(context.TODO(), node, metav1.CreateOptions{})
 	if err == nil {
+		kl.nodeStartupLatencyTracker.RecordRegisteredNewNode()
 		return true
 	}
 
@@ -633,6 +637,12 @@ func (kl *Kubelet) patchNodeStatus(originalNode, node *v1.Node) (*v1.Node, error
 	}
 	kl.lastStatusReportTime = kl.clock.Now()
 	kl.setLastObservedNodeAddresses(updatedNode.Status.Addresses)
+
+	readyIdx, readyCondition := nodeutil.GetNodeCondition(&updatedNode.Status, v1.NodeReady)
+	if readyIdx >= 0 && readyCondition.Status == v1.ConditionTrue {
+		kl.nodeStartupLatencyTracker.RecordNodeReady()
+	}
+
 	return updatedNode, nil
 }
 

pkg/kubelet/kubelet_test.go

@@ -268,6 +268,7 @@ func newTestKubeletWithImageList(
 	kubelet.podManager = kubepod.NewBasicPodManager()
 	podStartupLatencyTracker := kubeletutil.NewPodStartupLatencyTracker()
 	kubelet.statusManager = status.NewManager(fakeKubeClient, kubelet.podManager, &statustest.FakePodDeletionSafetyProvider{}, podStartupLatencyTracker, kubelet.getRootDir())
+	kubelet.nodeStartupLatencyTracker = kubeletutil.NewNodeStartupLatencyTracker()
 
 	kubelet.containerRuntime = fakeRuntime
 	kubelet.runtimeCache = containertest.NewFakeRuntimeCache(kubelet.containerRuntime)

pkg/kubelet/metrics/metrics.go

@@ -33,6 +33,11 @@ const (
 	KubeletSubsystem                   = "kubelet"
 	NodeNameKey                        = "node_name"
 	NodeLabelKey                       = "node"
+	NodeStartupPreKubeletKey           = "node_startup_pre_kubelet_duration_seconds"
+	NodeStartupPreRegistrationKey      = "node_startup_pre_registration_duration_seconds"
+	NodeStartupRegistrationKey         = "node_startup_registration_duration_seconds"
+	NodeStartupPostRegistrationKey     = "node_startup_post_registration_duration_seconds"
+	NodeStartupKey                     = "node_startup_duration_seconds"
 	PodWorkerDurationKey               = "pod_worker_duration_seconds"
 	PodStartDurationKey                = "pod_start_duration_seconds"
 	PodStartSLIDurationKey             = "pod_start_sli_duration_seconds"
@@ -736,6 +741,51 @@ var (
 			StabilityLevel: metrics.ALPHA,
 		},
 	)
+
+	NodeStartupPreKubeletDuration = metrics.NewGauge(
+		&metrics.GaugeOpts{
+			Subsystem:      KubeletSubsystem,
+			Name:           NodeStartupPreKubeletKey,
+			Help:           "Duration in seconds of node startup before kubelet starts.",
+			StabilityLevel: metrics.ALPHA,
+		},
+	)
+
+	NodeStartupPreRegistrationDuration = metrics.NewGauge(
+		&metrics.GaugeOpts{
+			Subsystem:      KubeletSubsystem,
+			Name:           NodeStartupPreRegistrationKey,
+			Help:           "Duration in seconds of node startup before registration.",
+			StabilityLevel: metrics.ALPHA,
+		},
+	)
+
+	NodeStartupRegistrationDuration = metrics.NewGauge(
+		&metrics.GaugeOpts{
+			Subsystem:      KubeletSubsystem,
+			Name:           NodeStartupRegistrationKey,
+			Help:           "Duration in seconds of node startup during registration.",
+			StabilityLevel: metrics.ALPHA,
+		},
+	)
+
+	NodeStartupPostRegistrationDuration = metrics.NewGauge(
+		&metrics.GaugeOpts{
+			Subsystem:      KubeletSubsystem,
+			Name:           NodeStartupPostRegistrationKey,
+			Help:           "Duration in seconds of node startup after registration.",
+			StabilityLevel: metrics.ALPHA,
+		},
+	)
+
+	NodeStartupDuration = metrics.NewGauge(
+		&metrics.GaugeOpts{
+			Subsystem:      KubeletSubsystem,
+			Name:           NodeStartupKey,
+			Help:           "Duration in seconds of node startup in total.",
+			StabilityLevel: metrics.ALPHA,
+		},
+	)
 )
 
 var registerMetrics sync.Once
@@ -748,6 +798,11 @@ func Register(collectors ...metrics.StableCollector) {
 		legacyregistry.MustRegister(PodWorkerDuration)
 		legacyregistry.MustRegister(PodStartDuration)
 		legacyregistry.MustRegister(PodStartSLIDuration)
+		legacyregistry.MustRegister(NodeStartupPreKubeletDuration)
+		legacyregistry.MustRegister(NodeStartupPreRegistrationDuration)
+		legacyregistry.MustRegister(NodeStartupRegistrationDuration)
+		legacyregistry.MustRegister(NodeStartupPostRegistrationDuration)
+		legacyregistry.MustRegister(NodeStartupDuration)
 		legacyregistry.MustRegister(CgroupManagerDuration)
 		legacyregistry.MustRegister(PodWorkerStartDuration)
 		legacyregistry.MustRegister(PodStatusSyncDuration)

pkg/kubelet/util/node_startup_latency_tracker.go

@@ -0,0 +1,103 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"sync"
+	"time"
+
+	"k8s.io/kubernetes/pkg/kubelet/metrics"
+	"k8s.io/utils/clock"
+)
+
+type NodeStartupLatencyTracker interface {
+	// This function may be called across Kubelet restart.
+	RecordAttemptRegisterNode()
+	// This function should not be called across Kubelet restart.
+	RecordRegisteredNewNode()
+	// This function may be called across Kubelet restart.
+	RecordNodeReady()
+}
+
+type basicNodeStartupLatencyTracker struct {
+	lock sync.Mutex
+
+	bootTime                     time.Time
+	kubeletStartTime             time.Time
+	firstRegistrationAttemptTime time.Time
+	firstRegisteredNewNodeTime   time.Time
+	firstNodeReadyTime           time.Time
+
+	// For testability
+	clock clock.Clock
+}
+
+func NewNodeStartupLatencyTracker() NodeStartupLatencyTracker {
+	bootTime, err := GetBootTime()
+	if err != nil {
+		bootTime = time.Time{}
+	}
+	return &basicNodeStartupLatencyTracker{
+		bootTime:         bootTime,
+		kubeletStartTime: time.Now(),
+		clock:            clock.RealClock{},
+	}
+}
+
+func (n *basicNodeStartupLatencyTracker) RecordAttemptRegisterNode() {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	if !n.firstRegistrationAttemptTime.IsZero() {
+		return
+	}
+
+	n.firstRegistrationAttemptTime = n.clock.Now()
+}
+
+func (n *basicNodeStartupLatencyTracker) RecordRegisteredNewNode() {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	if n.firstRegistrationAttemptTime.IsZero() || !n.firstRegisteredNewNodeTime.IsZero() {
+		return
+	}
+
+	n.firstRegisteredNewNodeTime = n.clock.Now()
+
+	if !n.bootTime.IsZero() {
+		metrics.NodeStartupPreKubeletDuration.Set(n.kubeletStartTime.Sub(n.bootTime).Seconds())
+	}
+	metrics.NodeStartupPreRegistrationDuration.Set(n.firstRegistrationAttemptTime.Sub(n.kubeletStartTime).Seconds())
+	metrics.NodeStartupRegistrationDuration.Set(n.firstRegisteredNewNodeTime.Sub(n.firstRegistrationAttemptTime).Seconds())
+}
+
+func (n *basicNodeStartupLatencyTracker) RecordNodeReady() {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	if n.firstRegisteredNewNodeTime.IsZero() || !n.firstNodeReadyTime.IsZero() {
+		return
+	}
+
+	n.firstNodeReadyTime = n.clock.Now()
+
+	metrics.NodeStartupPostRegistrationDuration.Set(n.firstNodeReadyTime.Sub(n.firstRegisteredNewNodeTime).Seconds())
+	if !n.bootTime.IsZero() {
+		metrics.NodeStartupDuration.Set(n.firstNodeReadyTime.Sub(n.bootTime).Seconds())
+	}
+}

pkg/kubelet/util/node_startup_latency_tracker_test.go

@@ -0,0 +1,418 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+
+	"k8s.io/component-base/metrics/testutil"
+	"k8s.io/kubernetes/pkg/kubelet/metrics"
+	"k8s.io/utils/clock"
+	testingclock "k8s.io/utils/clock/testing"
+)
+
+const (
+	metricsNameNodeStartupPreKubelet       = "kubelet_node_startup_pre_kubelet_duration_seconds"
+	metricsNameNodeStartupPreRegistration  = "kubelet_node_startup_pre_registration_duration_seconds"
+	metricsNameNodeStartupRegistration     = "kubelet_node_startup_registration_duration_seconds"
+	metricsNameNodeStartupPostRegistration = "kubelet_node_startup_post_registration_duration_seconds"
+	metricsNameNodeStartup                 = "kubelet_node_startup_duration_seconds"
+)
+
+func TestNodeStartupLatencyNoEvents(t *testing.T) {
+	t.Run("metrics registered; no incoming events", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            clock.RealClock{},
+		}
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 0
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 0
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0
+		`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+
+		assert.Equal(t, frozenTime.Add(-100*time.Millisecond), tracker.bootTime)
+		assert.Equal(t, frozenTime, tracker.kubeletStartTime)
+		assert.True(t, tracker.firstRegistrationAttemptTime.IsZero())
+		assert.True(t, tracker.firstRegisteredNewNodeTime.IsZero())
+		assert.True(t, tracker.firstNodeReadyTime.IsZero())
+	})
+}
+
+func TestRecordAllTimestamps(t *testing.T) {
+	t.Run("all timestamps are recorded", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(800 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		assert.Equal(t, frozenTime.Add(800*time.Millisecond), tracker.firstRegistrationAttemptTime)
+
+		fakeClock.Step(400 * time.Millisecond)
+		tracker.RecordRegisteredNewNode()
+
+		assert.Equal(t, frozenTime.Add(1200*time.Millisecond), tracker.firstRegisteredNewNodeTime)
+
+		fakeClock.Step(1100 * time.Millisecond)
+		tracker.RecordNodeReady()
+
+		assert.Equal(t, frozenTime.Add(2300*time.Millisecond), tracker.firstNodeReadyTime)
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 2.4
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 1.1
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0.1
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0.8
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0.4
+		`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+	})
+}
+
+func TestRecordAttemptRegister(t *testing.T) {
+	t.Run("record attempt register node", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(600 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		assert.Equal(t, frozenTime.Add(600*time.Millisecond), tracker.firstRegistrationAttemptTime)
+		assert.True(t, tracker.firstRegisteredNewNodeTime.IsZero())
+		assert.True(t, tracker.firstNodeReadyTime.IsZero())
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 0
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 0
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0
+				`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+	})
+}
+
+func TestRecordAttemptRegisterTwice(t *testing.T) {
+	t.Run("record attempt register node twice", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(600 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		fakeClock.Step(300 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		assert.Equal(t, frozenTime.Add(600*time.Millisecond), tracker.firstRegistrationAttemptTime)
+		assert.True(t, tracker.firstRegisteredNewNodeTime.IsZero())
+		assert.True(t, tracker.firstNodeReadyTime.IsZero())
+	})
+}
+
+func TestSkippingRecordRegisteredNewNode(t *testing.T) {
+	t.Run("record register new node twice", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(100 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		fakeClock.Step(500 * time.Millisecond)
+		tracker.RecordRegisteredNewNode()
+
+		fakeClock.Step(300 * time.Millisecond)
+		tracker.RecordRegisteredNewNode()
+
+		assert.Equal(t, frozenTime.Add(600*time.Millisecond), tracker.firstRegisteredNewNodeTime)
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 0
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 0
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0.1
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0.1
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0.5
+		`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+	})
+
+	t.Run("record register new node without previous step", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(700 * time.Millisecond)
+		tracker.RecordRegisteredNewNode()
+
+		assert.True(t, tracker.firstRegisteredNewNodeTime.IsZero())
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 0
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 0
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0
+		`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+	})
+}
+
+func TestSkippingRecordNodeReady(t *testing.T) {
+	t.Run("record node ready twice", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(100 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		fakeClock.Step(200 * time.Millisecond)
+		tracker.RecordRegisteredNewNode()
+
+		fakeClock.Step(300 * time.Millisecond)
+		tracker.RecordNodeReady()
+
+		fakeClock.Step(700 * time.Millisecond)
+		tracker.RecordNodeReady()
+
+		assert.Equal(t, frozenTime.Add(600*time.Millisecond), tracker.firstNodeReadyTime)
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 0.7
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 0.3
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0.1
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0.1
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0.2
+		`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+	})
+
+	t.Run("record node ready without previous step", func(t *testing.T) {
+		metrics.Register()
+		defer clearMetrics()
+
+		fakeClock := testingclock.NewFakeClock(frozenTime)
+		tracker := &basicNodeStartupLatencyTracker{
+			bootTime:         frozenTime.Add(-100 * time.Millisecond),
+			kubeletStartTime: frozenTime,
+			clock:            fakeClock,
+		}
+
+		fakeClock.Step(100 * time.Millisecond)
+		tracker.RecordAttemptRegisterNode()
+
+		fakeClock.Step(700 * time.Millisecond)
+		tracker.RecordNodeReady()
+
+		assert.True(t, tracker.firstNodeReadyTime.IsZero())
+
+		wants := `
+		# HELP kubelet_node_startup_duration_seconds [ALPHA] Duration in seconds of node startup in total.
+        # TYPE kubelet_node_startup_duration_seconds gauge
+        kubelet_node_startup_duration_seconds 0
+        # HELP kubelet_node_startup_post_registration_duration_seconds [ALPHA] Duration in seconds of node startup after registration.
+        # TYPE kubelet_node_startup_post_registration_duration_seconds gauge
+        kubelet_node_startup_post_registration_duration_seconds 0
+        # HELP kubelet_node_startup_pre_kubelet_duration_seconds [ALPHA] Duration in seconds of node startup before kubelet starts.
+        # TYPE kubelet_node_startup_pre_kubelet_duration_seconds gauge
+        kubelet_node_startup_pre_kubelet_duration_seconds 0
+        # HELP kubelet_node_startup_pre_registration_duration_seconds [ALPHA] Duration in seconds of node startup before registration.
+        # TYPE kubelet_node_startup_pre_registration_duration_seconds gauge
+        kubelet_node_startup_pre_registration_duration_seconds 0
+        # HELP kubelet_node_startup_registration_duration_seconds [ALPHA] Duration in seconds of node startup during registration.
+        # TYPE kubelet_node_startup_registration_duration_seconds gauge
+        kubelet_node_startup_registration_duration_seconds 0
+		`
+		if err := testutil.GatherAndCompare(metrics.GetGather(), strings.NewReader(wants),
+			metricsNameNodeStartupPreKubelet,
+			metricsNameNodeStartupPreRegistration,
+			metricsNameNodeStartupRegistration,
+			metricsNameNodeStartupPostRegistration,
+			metricsNameNodeStartup,
+		); err != nil {
+			t.Error(err)
+		}
+	})
+}
+
+func clearMetrics() {
+	metrics.NodeStartupPreKubeletDuration.Set(0)
+	metrics.NodeStartupPreRegistrationDuration.Set(0)
+	metrics.NodeStartupRegistrationDuration.Set(0)
+	metrics.NodeStartupPostRegistrationDuration.Set(0)
+	metrics.NodeStartupDuration.Set(0)
+}

pkg/kubemark/hollow_kubelet.go

@@ -113,6 +113,7 @@ func NewHollowKubelet(
 		Subpather:                 &subpath.FakeSubpath{},
 		HostUtil:                  hostutil.NewFakeHostUtil(nil),
 		PodStartupLatencyTracker:  kubeletutil.NewPodStartupLatencyTracker(),
+		NodeStartupLatencyTracker: kubeletutil.NewNodeStartupLatencyTracker(),
 		TracerProvider:            trace.NewNoopTracerProvider(),
 		Recorder:                  &record.FakeRecorder{}, // With real recorder we attempt to read /dev/kmsg.
 	}