[KEP-2400] kubectl top: add a --show-swap option (#129458)

* top, refactor: turn package-exposed variables to unexpose struct fields Signed-off-by: Itamar Holder <iholder@redhat.com> * kubectl top node: add the --show-swap option Example output: > kubectl top node --show-swap NAME CPU(cores) CPU(%) MEMORY(bytes) MEMORY(%) SWAP(bytes) SWAP(%) node01 500m 8% 2836Mi 60% 0Mi 0% node02 260m 5% 2206Mi 47% 512Mi 50% Signed-off-by: Itamar Holder <iholder@redhat.com> * kubectl top pod: add the --show-swap option Example output: > kubectl top pod -n kube-system --show-swap NAME CPU(cores) MEMORY(bytes) SWAP(bytes) coredns-58d5bc5cdb-5nbk4 2m 19Mi 0Mi coredns-58d5bc5cdb-jsh26 3m 37Mi 0Mi etcd-node01 51m 143Mi 0Mi kube-apiserver-node01 98m 824Mi 0Mi kube-controller-manager-node01 20m 135Mi 0Mi kube-proxy-ffgs2 1m 24Mi 0Mi kube-proxy-fhvwx 1m 39Mi 0Mi kube-scheduler-node01 13m 69Mi 0Mi metrics-server-8598789fdb-d2kcj 5m 26Mi 0Mi Signed-off-by: Itamar Holder <iholder@redhat.com> * kubectl top node --show-swap: add unit tests Signed-off-by: Itamar Holder <iholder@redhat.com> * kubectl top pod --show-swap: Add unit tests Signed-off-by: Itamar Holder <iholder@redhat.com> * Explicitly mark swap as unavailable when necessary Signed-off-by: Itamar Holder <iholder@redhat.com> --------- Signed-off-by: Itamar Holder <iholder@redhat.com>
2026-01-27 18:19:28 +00:00 · 2025-06-04 17:10:38 +03:00
parent caa9324842
commit 8d3fb9ee0a
8 changed files with 327 additions and 48 deletions
--- a/staging/src/k8s.io/kubectl/pkg/cmd/top/top_node.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/top/top_node.go
@@ -19,9 +19,9 @@ package top
 import (
 	"context"
 	"errors"
-
 	"github.com/spf13/cobra"
 	v1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/cli-runtime/pkg/genericiooptions"
@@ -45,6 +45,7 @@ type TopNodeOptions struct {
 	NoHeaders          bool
 	UseProtocolBuffers bool
 	ShowCapacity       bool
+	ShowSwap           bool

 	NodeClient      corev1client.CoreV1Interface
 	Printer         *metricsutil.TopCmdPrinter
@@ -95,6 +96,7 @@ func NewCmdTopNode(f cmdutil.Factory, o *TopNodeOptions, streams genericiooption
 	cmd.Flags().BoolVar(&o.NoHeaders, "no-headers", o.NoHeaders, "If present, print output without headers")
 	cmd.Flags().BoolVar(&o.UseProtocolBuffers, "use-protocol-buffers", o.UseProtocolBuffers, "Enables using protocol-buffers to access Metrics API.")
 	cmd.Flags().BoolVar(&o.ShowCapacity, "show-capacity", o.ShowCapacity, "Print node resources based on Capacity instead of Allocatable(default) of the nodes.")
+	cmd.Flags().BoolVar(&o.ShowSwap, "show-swap", o.ShowSwap, "Print node resources related to swap memory.")

 	return cmd
 }
@@ -127,7 +129,7 @@ func (o *TopNodeOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args []

 	o.NodeClient = clientset.CoreV1()

-	o.Printer = metricsutil.NewTopCmdPrinter(o.Out)
+	o.Printer = metricsutil.NewTopCmdPrinter(o.Out, o.ShowSwap)
 	return nil
 }

@@ -198,6 +200,14 @@ func (o TopNodeOptions) RunTopNode() error {
 		} else {
 			availableResources[n.Name] = n.Status.Capacity
 		}
+
+		if n.Status.NodeInfo.Swap != nil && n.Status.NodeInfo.Swap.Capacity != nil {
+			swapCapacity := *n.Status.NodeInfo.Swap.Capacity
+			availableResources[n.Name]["swap"] = *resource.NewQuantity(swapCapacity, resource.BinarySI)
+		} else {
+			o.Printer.RegisterMissingResource(n.Name, metricsutil.ResourceSwap)
+		}
+
 	}

 	return o.Printer.PrintNodeMetrics(metrics.Items, availableResources, o.NoHeaders, o.SortBy)
--- a/staging/src/k8s.io/kubectl/pkg/cmd/top/top_node_test.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/top/top_node_test.go
@@ -424,3 +424,111 @@ func TestTopNodeWithSortByMemoryMetricsFrom(t *testing.T) {
 	}

 }
+
+func TestTopNodeWithSwap(t *testing.T) {
+	runTopCmd := func(expectedMetrics *metricsv1beta1api.NodeMetricsList, nodes *v1.NodeList) (result string) {
+		cmdtesting.InitTestErrorHandler(t)
+		expectedNodePath := fmt.Sprintf("/%s/%s/nodes", apiPrefix, apiVersion)
+
+		tf := cmdtesting.NewTestFactory().WithNamespace("test")
+		defer tf.Cleanup()
+
+		codec := scheme.Codecs.LegacyCodec(scheme.Scheme.PrioritizedVersionsAllGroups()...)
+		ns := scheme.Codecs.WithoutConversion()
+
+		tf.Client = &fake.RESTClient{
+			NegotiatedSerializer: ns,
+			Client: fake.CreateHTTPClient(func(req *http.Request) (*http.Response, error) {
+				switch p, m := req.URL.Path, req.Method; {
+				case p == "/api":
+					return &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: io.NopCloser(bytes.NewReader([]byte(apibody)))}, nil
+				case p == "/apis":
+					return &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: io.NopCloser(bytes.NewReader([]byte(apisbodyWithMetrics)))}, nil
+				case p == expectedNodePath && m == "GET":
+					return &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: cmdtesting.ObjBody(codec, nodes)}, nil
+				default:
+					t.Fatalf("unexpected request: %#v\nGot URL: %#v\n", req, req.URL)
+					return nil, nil
+				}
+			}),
+		}
+		fakemetricsClientset := &metricsfake.Clientset{}
+		fakemetricsClientset.AddReactor("list", "nodes", func(action core.Action) (handled bool, ret runtime.Object, err error) {
+			return true, expectedMetrics, nil
+		})
+		tf.ClientConfigVal = cmdtesting.DefaultClientConfig()
+		streams, _, buf, _ := genericiooptions.NewTestIOStreams()
+
+		cmd := NewCmdTopNode(tf, nil, streams)
+
+		// TODO in the long run, we want to test most of our commands like this. Wire the options struct with specific mocks
+		// TODO then check the particular Run functionality and harvest results from fake clients
+		cmdOptions := &TopNodeOptions{
+			IOStreams: streams,
+			ShowSwap:  true,
+		}
+		if err := cmdOptions.Complete(tf, cmd, []string{}); err != nil {
+			t.Fatal(err)
+		}
+		cmdOptions.MetricsClient = fakemetricsClientset
+		if err := cmdOptions.Validate(); err != nil {
+			t.Fatal(err)
+		}
+		if err := cmdOptions.RunTopNode(); err != nil {
+			t.Fatal(err)
+		}
+
+		return buf.String()
+	}
+
+	for _, tc := range []struct {
+		name                  string
+		isSwapDisabledOnNodes bool
+	}{
+		{
+			name:                  "nodes with swap",
+			isSwapDisabledOnNodes: false,
+		},
+		{
+			name:                  "nodes without swap",
+			isSwapDisabledOnNodes: true,
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			expectedMetrics, nodes := testNodeV1beta1MetricsData()
+			if tc.isSwapDisabledOnNodes {
+				for i := range expectedMetrics.Items {
+					delete(expectedMetrics.Items[i].Usage, "swap")
+				}
+				for i := range nodes.Items {
+					nodes.Items[i].Status.NodeInfo.Swap = nil
+				}
+			}
+
+			result := runTopCmd(expectedMetrics, nodes)
+			fmt.Printf("%s\n", result)
+
+			if !strings.Contains(result, "SWAP(bytes)") {
+				t.Errorf("missing SWAP(bytes) header: \n%s", result)
+			}
+			if !strings.Contains(result, "SWAP(%)") {
+				t.Errorf("missing SWAP(%%) header: \n%s", result)
+			}
+
+			if tc.isSwapDisabledOnNodes {
+				if !strings.Contains(result, "<unknown>") {
+					t.Errorf("expected swap to be <unknown>: \n%s", result)
+				}
+			}
+
+			for _, m := range expectedMetrics.Items {
+				if !strings.Contains(result, m.Name) {
+					t.Errorf("missing metrics for %s: \n%s", m.Name, result)
+				}
+				if _, foundSwapMetric := m.Usage["swap"]; foundSwapMetric != !tc.isSwapDisabledOnNodes {
+					t.Errorf("missing swap metric for %s: \n%s", m.Name, result)
+				}
+			}
+		})
+	}
+}
--- a/staging/src/k8s.io/kubectl/pkg/cmd/top/top_pod.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/top/top_pod.go
@@ -53,6 +53,7 @@ type TopPodOptions struct {
 	NoHeaders          bool
 	UseProtocolBuffers bool
 	Sum                bool
+	ShowSwap           bool

 	PodClient       corev1client.PodsGetter
 	Printer         *metricsutil.TopCmdPrinter
@@ -117,6 +118,7 @@ func NewCmdTopPod(f cmdutil.Factory, o *TopPodOptions, streams genericiooptions.
 	cmd.Flags().BoolVar(&o.NoHeaders, "no-headers", o.NoHeaders, "If present, print output without headers.")
 	cmd.Flags().BoolVar(&o.UseProtocolBuffers, "use-protocol-buffers", o.UseProtocolBuffers, "Enables using protocol-buffers to access Metrics API.")
 	cmd.Flags().BoolVar(&o.Sum, "sum", o.Sum, "Print the sum of the resource usage")
+	cmd.Flags().BoolVar(&o.ShowSwap, "show-swap", o.ShowSwap, "Print pod resources related to swap memory.")
 	return cmd
 }

@@ -152,7 +154,7 @@ func (o *TopPodOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args []s

 	o.PodClient = clientset.CoreV1()

-	o.Printer = metricsutil.NewTopCmdPrinter(o.Out)
+	o.Printer = metricsutil.NewTopCmdPrinter(o.Out, o.ShowSwap)
 	return nil
 }

--- a/staging/src/k8s.io/kubectl/pkg/cmd/top/top_pod_test.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/top/top_pod_test.go
@@ -168,6 +168,12 @@ func TestTopPod(t *testing.T) {
 			namespaces: []string{testNS, testNS, testNS},
 			containers: true,
 		},
+		{
+			name:            "with swap",
+			options:         &TopPodOptions{AllNamespaces: true, ShowSwap: true},
+			namespaces:      []string{testNS, "secondtestns", "thirdtestns"},
+			listsNamespaces: true,
+		},
 	}
 	cmdtesting.InitTestErrorHandler(t)
 	for _, testCase := range testCases {
@@ -284,10 +290,101 @@ func TestTopPod(t *testing.T) {
 					t.Errorf("containers not matching:\n\texpectedContainers: %v\n\tresultContainers: %v\n", testCase.expectedContainers, resultContainers)
 				}
 			}
+			if testCase.options != nil && testCase.options.ShowSwap {
+				if !strings.Contains(result, "SWAP(bytes)") {
+					t.Errorf("missing SWAP(bytes) header: \n%s", result)
+				}
+			}
 		})
 	}
 }

+func TestTopPodWithSwap(t *testing.T) {
+	cmdtesting.InitTestErrorHandler(t)
+
+	const testName = "TestTopPodWithSwap"
+	t.Run(testName, func(t *testing.T) {
+		metricsList := testV1beta1PodMetricsData()
+		fakemetricsClientset := &metricsfake.Clientset{}
+
+		fakemetricsClientset.AddReactor("list", "pods", func(action core.Action) (handled bool, ret runtime.Object, err error) {
+			res := &metricsv1beta1api.PodMetricsList{
+				Items: metricsList,
+			}
+			return true, res, nil
+		})
+
+		tf := cmdtesting.NewTestFactory()
+		defer tf.Cleanup()
+
+		ns := scheme.Codecs.WithoutConversion()
+
+		tf.Client = &fake.RESTClient{
+			NegotiatedSerializer: ns,
+			Client: fake.CreateHTTPClient(func(req *http.Request) (*http.Response, error) {
+				switch req.URL.Path {
+				case "/api":
+					return &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: io.NopCloser(bytes.NewReader([]byte(apibody)))}, nil
+				case "/apis":
+					return &http.Response{StatusCode: http.StatusOK, Header: cmdtesting.DefaultHeader(), Body: io.NopCloser(bytes.NewReader([]byte(apisbodyWithMetrics)))}, nil
+				default:
+					t.Fatalf("%s: unexpected request: %#v\nGot URL: %#v",
+						testName, req, req.URL)
+					return nil, nil
+				}
+			}),
+		}
+		streams, _, buf, _ := genericiooptions.NewTestIOStreams()
+
+		cmd := NewCmdTopPod(tf, nil, streams)
+		cmdOptions := &TopPodOptions{
+			ShowSwap: true,
+		}
+		cmdOptions.IOStreams = streams
+
+		if err := cmdOptions.Complete(tf, cmd, nil); err != nil {
+			t.Fatal(err)
+		}
+		cmdOptions.MetricsClient = fakemetricsClientset
+		if err := cmdOptions.Validate(); err != nil {
+			t.Fatal(err)
+		}
+		if err := cmdOptions.RunTopPod(); err != nil {
+			t.Fatal(err)
+		}
+
+		result := buf.String()
+
+		expectedSwapBytes := map[string]string{
+			"pod1": "4Mi",
+			"pod2": "0Mi",
+			"pod3": "3Mi",
+		}
+
+		actualSwapBytes := map[string]string{}
+		for _, line := range strings.Split(result, "\n")[1:] {
+			lineFields := strings.Fields(line)
+			if len(lineFields) < 4 {
+				continue
+			}
+
+			podName := lineFields[0]
+			swapBytes := lineFields[3]
+			actualSwapBytes[podName] = swapBytes
+		}
+
+		for expectedPodName, expectedSwapBytes := range expectedSwapBytes {
+			actualSwapBytes, found := actualSwapBytes[expectedPodName]
+			if !found {
+				t.Errorf("missing swap metrics for pod %s", expectedPodName)
+			}
+			if actualSwapBytes != expectedSwapBytes {
+				t.Errorf("unexpected swap metrics for pod %s: expected %s, got %s", expectedPodName, expectedSwapBytes, actualSwapBytes)
+			}
+		}
+	})
+}
+
 func getResultColumnValues(result string, columnIndex int) []string {
 	resultLines := strings.Split(result, "\n")
 	values := make([]string, len(resultLines)-2) // don't process first (header) and last (empty) line
@@ -410,6 +507,7 @@ func testV1beta1PodMetricsData() []metricsv1beta1api.PodMetrics {
 					Usage: v1.ResourceList{
 						v1.ResourceCPU:     *resource.NewMilliQuantity(1, resource.DecimalSI),
 						v1.ResourceMemory:  *resource.NewQuantity(2*(1024*1024), resource.DecimalSI),
+						"swap":             *resource.NewQuantity(1*(1024*1024), resource.DecimalSI),
 						v1.ResourceStorage: *resource.NewQuantity(3*(1024*1024), resource.DecimalSI),
 					},
 				},
@@ -418,6 +516,7 @@ func testV1beta1PodMetricsData() []metricsv1beta1api.PodMetrics {
 					Usage: v1.ResourceList{
 						v1.ResourceCPU:     *resource.NewMilliQuantity(4, resource.DecimalSI),
 						v1.ResourceMemory:  *resource.NewQuantity(5*(1024*1024), resource.DecimalSI),
+						"swap":             *resource.NewQuantity(3*(1024*1024), resource.DecimalSI),
 						v1.ResourceStorage: *resource.NewQuantity(6*(1024*1024), resource.DecimalSI),
 					},
 				},
@@ -462,6 +561,7 @@ func testV1beta1PodMetricsData() []metricsv1beta1api.PodMetrics {
 					Usage: v1.ResourceList{
 						v1.ResourceCPU:     *resource.NewMilliQuantity(7, resource.DecimalSI),
 						v1.ResourceMemory:  *resource.NewQuantity(8*(1024*1024), resource.DecimalSI),
+						"swap":             *resource.NewQuantity(3*(1024*1024), resource.DecimalSI),
 						v1.ResourceStorage: *resource.NewQuantity(9*(1024*1024), resource.DecimalSI),
 					},
 				},
--- a/staging/src/k8s.io/kubectl/pkg/cmd/top/top_test.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/top/top_test.go
@@ -30,6 +30,7 @@ import (
 	"k8s.io/cli-runtime/pkg/genericiooptions"
 	cmdtesting "k8s.io/kubectl/pkg/cmd/testing"
 	metricsv1beta1api "k8s.io/metrics/pkg/apis/metrics/v1beta1"
+	"k8s.io/utils/ptr"
 )

 func TestTopSubcommandsExist(t *testing.T) {
@@ -63,6 +64,7 @@ func testNodeV1beta1MetricsData() (*metricsv1beta1api.NodeMetricsList, *v1.NodeL
 				Window:     metav1.Duration{Duration: time.Minute},
 				Usage: v1.ResourceList{
 					v1.ResourceCPU:     *resource.NewMilliQuantity(1, resource.DecimalSI),
+					"swap":             *resource.NewQuantity(1*(1024*1024), resource.DecimalSI),
 					v1.ResourceMemory:  *resource.NewQuantity(2*(1024*1024), resource.DecimalSI),
 					v1.ResourceStorage: *resource.NewQuantity(3*(1024*1024), resource.DecimalSI),
 				},
@@ -72,6 +74,7 @@ func testNodeV1beta1MetricsData() (*metricsv1beta1api.NodeMetricsList, *v1.NodeL
 				Window:     metav1.Duration{Duration: time.Minute},
 				Usage: v1.ResourceList{
 					v1.ResourceCPU:     *resource.NewMilliQuantity(5, resource.DecimalSI),
+					"swap":             *resource.NewQuantity(2*(1024*1024), resource.DecimalSI),
 					v1.ResourceMemory:  *resource.NewQuantity(6*(1024*1024), resource.DecimalSI),
 					v1.ResourceStorage: *resource.NewQuantity(7*(1024*1024), resource.DecimalSI),
 				},
@@ -81,6 +84,7 @@ func testNodeV1beta1MetricsData() (*metricsv1beta1api.NodeMetricsList, *v1.NodeL
 				Window:     metav1.Duration{Duration: time.Minute},
 				Usage: v1.ResourceList{
 					v1.ResourceCPU:     *resource.NewMilliQuantity(3, resource.DecimalSI),
+					"swap":             *resource.NewQuantity(0, resource.DecimalSI),
 					v1.ResourceMemory:  *resource.NewQuantity(4*(1024*1024), resource.DecimalSI),
 					v1.ResourceStorage: *resource.NewQuantity(5*(1024*1024), resource.DecimalSI),
 				},
@@ -100,6 +104,11 @@ func testNodeV1beta1MetricsData() (*metricsv1beta1api.NodeMetricsList, *v1.NodeL
 						v1.ResourceMemory:  *resource.NewQuantity(20*(1024*1024), resource.DecimalSI),
 						v1.ResourceStorage: *resource.NewQuantity(30*(1024*1024), resource.DecimalSI),
 					},
+					NodeInfo: v1.NodeSystemInfo{
+						Swap: &v1.NodeSwapStatus{
+							Capacity: ptr.To(int64(10 * (1024 * 1024 * 1024))),
+						},
+					},
 				},
 			},
 			{
@@ -110,6 +119,11 @@ func testNodeV1beta1MetricsData() (*metricsv1beta1api.NodeMetricsList, *v1.NodeL
 						v1.ResourceMemory:  *resource.NewQuantity(60*(1024*1024), resource.DecimalSI),
 						v1.ResourceStorage: *resource.NewQuantity(70*(1024*1024), resource.DecimalSI),
 					},
+					NodeInfo: v1.NodeSystemInfo{
+						Swap: &v1.NodeSwapStatus{
+							Capacity: ptr.To(int64(20 * (1024 * 1024 * 1024))),
+						},
+					},
 				},
 			},
 			{
@@ -120,6 +134,11 @@ func testNodeV1beta1MetricsData() (*metricsv1beta1api.NodeMetricsList, *v1.NodeL
 						v1.ResourceMemory:  *resource.NewQuantity(40*(1024*1024), resource.DecimalSI),
 						v1.ResourceStorage: *resource.NewQuantity(50*(1024*1024), resource.DecimalSI),
 					},
+					NodeInfo: v1.NodeSystemInfo{
+						Swap: &v1.NodeSwapStatus{
+							Capacity: ptr.To(int64(30 * (1024 * 1024 * 1024))),
+						},
+					},
 				},
 			},
 		},
--- a/staging/src/k8s.io/kubectl/pkg/metricsutil/metrics_printer.go
+++ b/staging/src/k8s.io/kubectl/pkg/metricsutil/metrics_printer.go
@@ -19,6 +19,7 @@ package metricsutil
 import (
 	"fmt"
 	"io"
+	"slices"
 	"sort"

 	"k8s.io/api/core/v1"
@@ -28,16 +29,12 @@ import (
 )

 var (
-	MeasuredResources = []v1.ResourceName{
-		v1.ResourceCPU,
-		v1.ResourceMemory,
-	}
-	NodeColumns     = []string{"NAME", "CPU(cores)", "CPU(%)", "MEMORY(bytes)", "MEMORY(%)"}
-	PodColumns      = []string{"NAME", "CPU(cores)", "MEMORY(bytes)"}
 	NamespaceColumn = "NAMESPACE"
 	PodColumn       = "POD"
 )

+const ResourceSwap = "swap"
+
 type ResourceMetricsInfo struct {
 	Name      string
 	Metrics   v1.ResourceList
@@ -45,11 +42,33 @@ type ResourceMetricsInfo struct {
 }

 type TopCmdPrinter struct {
-	out io.Writer
+	out               io.Writer
+	measuredResources []v1.ResourceName
+	nodeColumns       []string
+	podColumns        []string
+	// a map from a node name to its missing resources
+	nodesMissingResources map[string][]string
 }

-func NewTopCmdPrinter(out io.Writer) *TopCmdPrinter {
-	return &TopCmdPrinter{out: out}
+func NewTopCmdPrinter(out io.Writer, showSwap bool) *TopCmdPrinter {
+	printer := &TopCmdPrinter{
+		out: out,
+		measuredResources: []v1.ResourceName{
+			v1.ResourceCPU,
+			v1.ResourceMemory,
+		},
+		nodeColumns:           []string{"NAME", "CPU(cores)", "CPU(%)", "MEMORY(bytes)", "MEMORY(%)"},
+		podColumns:            []string{"NAME", "CPU(cores)", "MEMORY(bytes)"},
+		nodesMissingResources: make(map[string][]string),
+	}
+
+	if showSwap {
+		printer.measuredResources = append(printer.measuredResources, ResourceSwap)
+		printer.nodeColumns = append(printer.nodeColumns, "SWAP(bytes)", "SWAP(%)")
+		printer.podColumns = append(printer.podColumns, "SWAP(bytes)")
+	}
+
+	return printer
 }

 func (printer *TopCmdPrinter) PrintNodeMetrics(metrics []metricsapi.NodeMetrics, availableResources map[string]v1.ResourceList, noHeaders bool, sortBy string) error {
@@ -59,25 +78,26 @@ func (printer *TopCmdPrinter) PrintNodeMetrics(metrics []metricsapi.NodeMetrics,
 	w := printers.GetNewTabWriter(printer.out)
 	defer w.Flush()

+	measuredResources := printer.measuredResources
 	sort.Sort(NewNodeMetricsSorter(metrics, sortBy))

 	if !noHeaders {
-		printColumnNames(w, NodeColumns)
+		printColumnNames(w, printer.nodeColumns)
 	}
 	var usage v1.ResourceList
 	for _, m := range metrics {
 		m.Usage.DeepCopyInto(&usage)
-		printMetricsLine(w, &ResourceMetricsInfo{
+		printer.printMetricsLine(w, &ResourceMetricsInfo{
 			Name:      m.Name,
 			Metrics:   usage,
 			Available: availableResources[m.Name],
-		})
+		}, measuredResources)
 		delete(availableResources, m.Name)
 	}

 	// print lines for nodes of which the metrics is unreachable.
 	for nodeName := range availableResources {
-		printMissingMetricsNodeLine(w, nodeName)
+		printer.printMissingMetricsNodeLine(w, nodeName, measuredResources)
 	}
 	return nil
 }
@@ -89,7 +109,7 @@ func (printer *TopCmdPrinter) PrintPodMetrics(metrics []metricsapi.PodMetrics, p
 	w := printers.GetNewTabWriter(printer.out)
 	defer w.Flush()

-	columnWidth := len(PodColumns)
+	columnWidth := len(printer.podColumns)
 	if !noHeaders {
 		if withNamespace {
 			printValue(w, NamespaceColumn)
@@ -99,32 +119,39 @@ func (printer *TopCmdPrinter) PrintPodMetrics(metrics []metricsapi.PodMetrics, p
 			printValue(w, PodColumn)
 			columnWidth++
 		}
-		printColumnNames(w, PodColumns)
+		printColumnNames(w, printer.podColumns)
 	}

-	sort.Sort(NewPodMetricsSorter(metrics, withNamespace, sortBy))
+	sort.Sort(NewPodMetricsSorter(metrics, withNamespace, sortBy, printer.measuredResources))

 	for _, m := range metrics {
 		if printContainers {
 			sort.Sort(NewContainerMetricsSorter(m.Containers, sortBy))
-			printSinglePodContainerMetrics(w, &m, withNamespace)
+			printer.printSinglePodContainerMetrics(w, &m, withNamespace, printer.measuredResources)
 		} else {
-			printSinglePodMetrics(w, &m, withNamespace)
+			printer.printSinglePodMetrics(w, &m, withNamespace, printer.measuredResources)
 		}

 	}

 	if sum {
-		adder := NewResourceAdder(MeasuredResources)
+		adder := NewResourceAdder(printer.measuredResources)
 		for _, m := range metrics {
 			adder.AddPodMetrics(&m)
 		}
-		printPodResourcesSum(w, adder.total, columnWidth)
+		printer.printPodResourcesSum(w, adder.total, columnWidth, printer.measuredResources)
 	}

 	return nil
 }

+func (printer *TopCmdPrinter) RegisterMissingResource(nodeName, resourceName string) {
+	if slices.Contains(printer.nodesMissingResources[nodeName], resourceName) {
+		return
+	}
+	printer.nodesMissingResources[nodeName] = append(printer.nodesMissingResources[nodeName], resourceName)
+}
+
 func printColumnNames(out io.Writer, names []string) {
 	for _, name := range names {
 		printValue(out, name)
@@ -132,40 +159,40 @@ func printColumnNames(out io.Writer, names []string) {
 	fmt.Fprint(out, "\n")
 }

-func printSinglePodMetrics(out io.Writer, m *metricsapi.PodMetrics, withNamespace bool) {
-	podMetrics := getPodMetrics(m)
+func (printer *TopCmdPrinter) printSinglePodMetrics(out io.Writer, m *metricsapi.PodMetrics, withNamespace bool, measuredResources []v1.ResourceName) {
+	podMetrics := getPodMetrics(m, measuredResources)
 	if withNamespace {
 		printValue(out, m.Namespace)
 	}
-	printMetricsLine(out, &ResourceMetricsInfo{
+	printer.printMetricsLine(out, &ResourceMetricsInfo{
 		Name:      m.Name,
 		Metrics:   podMetrics,
 		Available: v1.ResourceList{},
-	})
+	}, measuredResources)
 }

-func printSinglePodContainerMetrics(out io.Writer, m *metricsapi.PodMetrics, withNamespace bool) {
+func (printer *TopCmdPrinter) printSinglePodContainerMetrics(out io.Writer, m *metricsapi.PodMetrics, withNamespace bool, measuredResources []v1.ResourceName) {
 	for _, c := range m.Containers {
 		if withNamespace {
 			printValue(out, m.Namespace)
 		}
 		printValue(out, m.Name)
-		printMetricsLine(out, &ResourceMetricsInfo{
+		printer.printMetricsLine(out, &ResourceMetricsInfo{
 			Name:      c.Name,
 			Metrics:   c.Usage,
 			Available: v1.ResourceList{},
-		})
+		}, measuredResources)
 	}
 }

-func getPodMetrics(m *metricsapi.PodMetrics) v1.ResourceList {
+func getPodMetrics(m *metricsapi.PodMetrics, measuredResources []v1.ResourceName) v1.ResourceList {
 	podMetrics := make(v1.ResourceList)
-	for _, res := range MeasuredResources {
+	for _, res := range measuredResources {
 		podMetrics[res], _ = resource.ParseQuantity("0")
 	}

 	for _, c := range m.Containers {
-		for _, res := range MeasuredResources {
+		for _, res := range measuredResources {
 			quantity := podMetrics[res]
 			quantity.Add(c.Usage[res])
 			podMetrics[res] = quantity
@@ -174,16 +201,16 @@ func getPodMetrics(m *metricsapi.PodMetrics) v1.ResourceList {
 	return podMetrics
 }

-func printMetricsLine(out io.Writer, metrics *ResourceMetricsInfo) {
+func (printer *TopCmdPrinter) printMetricsLine(out io.Writer, metrics *ResourceMetricsInfo, measuredResources []v1.ResourceName) {
 	printValue(out, metrics.Name)
-	printAllResourceUsages(out, metrics)
+	printer.printAllResourceUsages(out, metrics, measuredResources)
 	fmt.Fprint(out, "\n")
 }

-func printMissingMetricsNodeLine(out io.Writer, nodeName string) {
+func (printer *TopCmdPrinter) printMissingMetricsNodeLine(out io.Writer, nodeName string, measuredResources []v1.ResourceName) {
 	printValue(out, nodeName)
 	unknownMetricsStatus := "<unknown>"
-	for i := 0; i < len(MeasuredResources); i++ {
+	for i := 0; i < len(measuredResources); i++ {
 		printValue(out, unknownMetricsStatus)
 		printValue(out, unknownMetricsStatus)
 	}
@@ -194,13 +221,21 @@ func printValue(out io.Writer, value interface{}) {
 	fmt.Fprintf(out, "%v\t", value)
 }

-func printAllResourceUsages(out io.Writer, metrics *ResourceMetricsInfo) {
-	for _, res := range MeasuredResources {
+func (printer *TopCmdPrinter) printAllResourceUsages(out io.Writer, metrics *ResourceMetricsInfo, measuredResources []v1.ResourceName) {
+	for _, res := range measuredResources {
+		if missingResources, found := printer.nodesMissingResources[metrics.Name]; found && slices.Contains(missingResources, string(res)) {
+			printSingleMissingResource(out)
+			continue
+		}
+
 		quantity := metrics.Metrics[res]
 		printSingleResourceUsage(out, res, quantity)
 		fmt.Fprint(out, "\t")
 		if available, found := metrics.Available[res]; found {
-			fraction := float64(quantity.MilliValue()) / float64(available.MilliValue()) * 100
+			fraction := 0.0
+			if !available.IsZero() {
+				fraction = float64(quantity.MilliValue()) / float64(available.MilliValue()) * 100
+			}
 			fmt.Fprintf(out, "%d%%\t", int64(fraction))
 		}
 	}
@@ -210,14 +245,19 @@ func printSingleResourceUsage(out io.Writer, resourceType v1.ResourceName, quant
 	switch resourceType {
 	case v1.ResourceCPU:
 		fmt.Fprintf(out, "%vm", quantity.MilliValue())
-	case v1.ResourceMemory:
+	case v1.ResourceMemory, ResourceSwap:
 		fmt.Fprintf(out, "%vMi", quantity.Value()/(1024*1024))
 	default:
 		fmt.Fprintf(out, "%v", quantity.Value())
 	}
 }

-func printPodResourcesSum(out io.Writer, total v1.ResourceList, columnWidth int) {
+func printSingleMissingResource(out io.Writer) {
+	const unavailableStr = "<unknown>"
+	_, _ = fmt.Fprintf(out, "%s\t%s\t", unavailableStr, unavailableStr)
+}
+
+func (printer *TopCmdPrinter) printPodResourcesSum(out io.Writer, total v1.ResourceList, columnWidth int, measuredResources []v1.ResourceName) {
 	for i := 0; i < columnWidth-2; i++ {
 		printValue(out, "")
 	}
@@ -227,10 +267,10 @@ func printPodResourcesSum(out io.Writer, total v1.ResourceList, columnWidth int)
 	for i := 0; i < columnWidth-3; i++ {
 		printValue(out, "")
 	}
-	printMetricsLine(out, &ResourceMetricsInfo{
+	printer.printMetricsLine(out, &ResourceMetricsInfo{
 		Name:      "",
 		Metrics:   total,
 		Available: v1.ResourceList{},
-	})
+	}, measuredResources)

 }
--- a/staging/src/k8s.io/kubectl/pkg/metricsutil/metrics_printer_test.go
+++ b/staging/src/k8s.io/kubectl/pkg/metricsutil/metrics_printer_test.go
@@ -130,7 +130,7 @@ node1   1000m        10%      1024Mi          10%
 			for _, n := range test.nodes {
 				availableResources[n.Name] = n.Status.Capacity
 			}
-			top := NewTopCmdPrinter(out)
+			top := NewTopCmdPrinter(out, false)
 			err := top.PrintNodeMetrics(test.nodeMetric, availableResources, test.noHeader, test.sortBy)
 			assert.Equal(t, test.expectedErr, err)
 			assert.Equal(t, test.expectedOutput, out.String())
@@ -374,7 +374,7 @@ test-1   400m         5120Mi
 			// Create a new TopCmdPrinter with a test writer.
 			_, _, out, _ := genericiooptions.NewTestIOStreams()

-			top := NewTopCmdPrinter(out)
+			top := NewTopCmdPrinter(out, false)
 			err := top.PrintPodMetrics(test.podMetric, test.printContainers,
 				test.withNamespace, test.noHeader, test.sortBy, test.sum)
 			assert.Equal(t, test.expectedErr, err)
--- a/staging/src/k8s.io/kubectl/pkg/metricsutil/metrics_sorter.go
+++ b/staging/src/k8s.io/kubectl/pkg/metricsutil/metrics_sorter.go
@@ -82,11 +82,11 @@ func (p *PodMetricsSorter) Less(i, j int) bool {
 	}
 }

-func NewPodMetricsSorter(metrics []metricsapi.PodMetrics, withNamespace bool, sortBy string) *PodMetricsSorter {
+func NewPodMetricsSorter(metrics []metricsapi.PodMetrics, withNamespace bool, sortBy string, measuredResources []v1.ResourceName) *PodMetricsSorter {
 	var podMetrics = make([]v1.ResourceList, len(metrics))
 	if len(sortBy) > 0 {
 		for i, v := range metrics {
-			podMetrics[i] = getPodMetrics(&v)
+			podMetrics[i] = getPodMetrics(&v, measuredResources)
 		}
 	}