Repository: kubernetes-sigs/descheduler (go)

Issue:
preEvictionFilter also filtering namespaces
Follow up from https://github.com/kubernetes-sigs/descheduler/issues/924, so users can also filter namespaces in strategies like LowNodeUtilization. 


Pull request:
add namespace filter to nodeutilization
Closes #966 



Patch:
diff --git a/README.md b/README.md
index 0bc94b0cb..ac2b2c656 100644
--- a/README.md
+++ b/README.md
@@ -243,6 +243,7 @@ actual usage metrics. Implementing metrics-based descheduling is currently TODO
 |`thresholdPriority`|int (see [priority filtering](#priority-filtering))|
 |`thresholdPriorityClassName`|string (see [priority filtering](#priority-filtering))|
 |`nodeFit`|bool (see [node fit filtering](#node-fit-filtering))|
+|`evictableNamespaces`|(see [namespace filtering](#namespace-filtering))|
 
 **Example:**
 
@@ -315,6 +316,7 @@ actual usage metrics. Implementing metrics-based descheduling is currently TODO
 |`thresholdPriority`|int (see [priority filtering](#priority-filtering))|
 |`thresholdPriorityClassName`|string (see [priority filtering](#priority-filtering))|
 |`nodeFit`|bool (see [node fit filtering](#node-fit-filtering))|
+|`evictableNamespaces`|(see [namespace filtering](#namespace-filtering))|
 
 **Example:**
 
@@ -613,6 +615,7 @@ The following strategies accept a `namespaces` parameter which allows to specify
 * `RemoveDuplicates`
 * `RemovePodsViolatingTopologySpreadConstraint`
 * `RemoveFailedPods`
+* `LowNodeUtilization` and `HighNodeUtilization` (Only filtered right before eviction, parameter named `evictableNamespaces`)
 
 For example:
 
diff --git a/cmd/descheduler/app/server.go b/cmd/descheduler/app/server.go
index 0f38d3e00..f060b3b94 100644
--- a/cmd/descheduler/app/server.go
+++ b/cmd/descheduler/app/server.go
@@ -34,7 +34,6 @@ import (
 	"k8s.io/apiserver/pkg/server/mux"
 	restclient "k8s.io/client-go/rest"
 	registry "k8s.io/component-base/logs/api/v1"
-	jsonLog "k8s.io/component-base/logs/json"
 	_ "k8s.io/component-base/logs/json/register"
 	"k8s.io/component-base/metrics/legacyregistry"
 	"k8s.io/klog/v2"
@@ -63,18 +62,13 @@ func NewDeschedulerCommand(out io.Writer) *cobra.Command {
 				return
 			}
 			var factory registry.LogFormatFactory
-
-			if s.Logging.Format == "json" {
-				factory = jsonLog.Factory{}
-			}
-
 			if factory == nil {
 				klog.ClearLogger()
 			} else {
 				log, logrFlush := factory.Create(registry.LoggingConfiguration{
-					Format:    s.Logging.Format,
-					Verbosity: s.Logging.Verbosity,
+					Format: s.Logging.Format,
 				})
+
 				defer logrFlush()
 				klog.SetLogger(log)
 			}
diff --git a/pkg/framework/plugins/nodeutilization/highnodeutilization.go b/pkg/framework/plugins/nodeutilization/highnodeutilization.go
index 0c3977153..fa6b83146 100644
--- a/pkg/framework/plugins/nodeutilization/highnodeutilization.go
+++ b/pkg/framework/plugins/nodeutilization/highnodeutilization.go
@@ -140,6 +140,7 @@ func (h *HighNodeUtilization) Balance(ctx context.Context, nodes []*v1.Node) *fr
 
 	evictPodsFromSourceNodes(
 		ctx,
+		h.args.EvictableNamespaces,
 		sourceNodes,
 		highNodes,
 		h.handle.Evictor(),
diff --git a/pkg/framework/plugins/nodeutilization/lownodeutilization.go b/pkg/framework/plugins/nodeutilization/lownodeutilization.go
index b11ff4dce..b750b1d7a 100644
--- a/pkg/framework/plugins/nodeutilization/lownodeutilization.go
+++ b/pkg/framework/plugins/nodeutilization/lownodeutilization.go
@@ -187,6 +187,7 @@ func (l *LowNodeUtilization) Balance(ctx context.Context, nodes []*v1.Node) *fra
 
 	evictPodsFromSourceNodes(
 		ctx,
+		l.args.EvictableNamespaces,
 		sourceNodes,
 		lowNodes,
 		l.handle.Evictor(),
diff --git a/pkg/framework/plugins/nodeutilization/nodeutilization.go b/pkg/framework/plugins/nodeutilization/nodeutilization.go
index 2b7ea4a2f..fe96068f9 100644
--- a/pkg/framework/plugins/nodeutilization/nodeutilization.go
+++ b/pkg/framework/plugins/nodeutilization/nodeutilization.go
@@ -24,6 +24,7 @@ import (
 
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/klog/v2"
 	"sigs.k8s.io/descheduler/pkg/descheduler/evictions"
 	"sigs.k8s.io/descheduler/pkg/descheduler/node"
@@ -212,6 +213,7 @@ func classifyNodes(
 // TODO: @ravig Break this function into smaller functions.
 func evictPodsFromSourceNodes(
 	ctx context.Context,
+	evictableNamespaces *api.Namespaces,
 	sourceNodes, destinationNodes []NodeInfo,
 	podEvictor framework.Evictor,
 	podFilter func(pod *v1.Pod) bool,
@@ -265,13 +267,14 @@ func evictPodsFromSourceNodes(
 		klog.V(1).InfoS("Evicting pods based on priority, if they have same priority, they'll be evicted based on QoS tiers")
 		// sort the evictable Pods based on priority. This also sorts them based on QoS. If there are multiple pods with same priority, they are sorted based on QoS tiers.
 		podutil.SortPodsBasedOnPriorityLowToHigh(removablePods)
-		evictPods(ctx, removablePods, node, totalAvailableUsage, taintsOfDestinationNodes, podEvictor, continueEviction)
+		evictPods(ctx, evictableNamespaces, removablePods, node, totalAvailableUsage, taintsOfDestinationNodes, podEvictor, continueEviction)
 
 	}
 }
 
 func evictPods(
 	ctx context.Context,
+	evictableNamespaces *api.Namespaces,
 	inputPods []*v1.Pod,
 	nodeInfo NodeInfo,
 	totalAvailableUsage map[v1.ResourceName]*resource.Quantity,
@@ -280,6 +283,11 @@ func evictPods(
 	continueEviction continueEvictionCond,
 ) {
 
+	var excludedNamespaces sets.String
+	if evictableNamespaces != nil {
+		excludedNamespaces = sets.NewString(evictableNamespaces.Exclude...)
+	}
+
 	if continueEviction(nodeInfo, totalAvailableUsage) {
 		for _, pod := range inputPods {
 			if !utils.PodToleratesTaints(pod, taintsOfLowNodes) {
@@ -287,7 +295,16 @@ func evictPods(
 				continue
 			}
 
-			if podEvictor.PreEvictionFilter(pod) {
+			preEvictionFilterWithOptions, err := podutil.NewOptions().
+				WithFilter(podEvictor.PreEvictionFilter).
+				WithoutNamespaces(excludedNamespaces).
+				BuildFilterFunc()
+			if err != nil {
+				klog.V(1).ErrorS(err, "could not build preEvictionFilter with namespace exclusion")
+				continue
+			}
+
+			if preEvictionFilterWithOptions(pod) {
 				if podEvictor.Evict(ctx, pod, evictions.EvictOptions{}) {
 					klog.V(3).InfoS("Evicted pods", "pod", klog.KObj(pod))
 
diff --git a/pkg/framework/plugins/nodeutilization/types.go b/pkg/framework/plugins/nodeutilization/types.go
index f850f6470..8bdd694c1 100644
--- a/pkg/framework/plugins/nodeutilization/types.go
+++ b/pkg/framework/plugins/nodeutilization/types.go
@@ -28,6 +28,10 @@ type LowNodeUtilizationArgs struct {
 	Thresholds             api.ResourceThresholds
 	TargetThresholds       api.ResourceThresholds
 	NumberOfNodes          int
+	// Naming this one differently since namespaces are still
+	// considered while considering resoures used by pods
+	// but then filtered out before eviction
+	EvictableNamespaces *api.Namespaces
 }
 
 // +k8s:deepcopy-gen=true
@@ -38,4 +42,8 @@ type HighNodeUtilizationArgs struct {
 
 	Thresholds    api.ResourceThresholds
 	NumberOfNodes int
+	// Naming this one differently since namespaces are still
+	// considered while considering resoures used by pods
+	// but then filtered out before eviction
+	EvictableNamespaces *api.Namespaces
 }
diff --git a/pkg/framework/plugins/nodeutilization/validation.go b/pkg/framework/plugins/nodeutilization/validation.go
index 89969a8d9..1dd273627 100644
--- a/pkg/framework/plugins/nodeutilization/validation.go
+++ b/pkg/framework/plugins/nodeutilization/validation.go
@@ -19,7 +19,16 @@ import (
 )
 
 func ValidateHighNodeUtilizationArgs(args *HighNodeUtilizationArgs) error {
-	return validateThresholds(args.Thresholds)
+	// only exclude can be set, or not at all
+	if args.EvictableNamespaces != nil && len(args.EvictableNamespaces.Include) > 0 {
+		return fmt.Errorf("only Exclude namespaces can be set, inclusion is not supported")
+	}
+	err := validateThresholds(args.Thresholds)
+	if err != nil {
+		return err
+	}
+
+	return nil
 }
 
 func ValidateLowNodeUtilizationArgs(args *LowNodeUtilizationArgs) error {
diff --git a/pkg/framework/plugins/nodeutilization/zz_generated.deepcopy.go b/pkg/framework/plugins/nodeutilization/zz_generated.deepcopy.go
index faab6a47c..efeab1816 100644
--- a/pkg/framework/plugins/nodeutilization/zz_generated.deepcopy.go
+++ b/pkg/framework/plugins/nodeutilization/zz_generated.deepcopy.go
@@ -37,6 +37,11 @@ func (in *HighNodeUtilizationArgs) DeepCopyInto(out *HighNodeUtilizationArgs) {
 			(*out)[key] = val
 		}
 	}
+	if in.EvictableNamespaces != nil {
+		in, out := &in.EvictableNamespaces, &out.EvictableNamespaces
+		*out = new(api.Namespaces)
+		(*in).DeepCopyInto(*out)
+	}
 	return
 }
 
@@ -76,6 +81,11 @@ func (in *LowNodeUtilizationArgs) DeepCopyInto(out *LowNodeUtilizationArgs) {
 			(*out)[key] = val
 		}
 	}
+	if in.EvictableNamespaces != nil {
+		in, out := &in.EvictableNamespaces, &out.EvictableNamespaces
+		*out = new(api.Namespaces)
+		(*in).DeepCopyInto(*out)
+	}
 	return
 }
 


Test patch:
diff --git a/pkg/framework/plugins/nodeutilization/lownodeutilization_test.go b/pkg/framework/plugins/nodeutilization/lownodeutilization_test.go
index 8cf7be5d8..a00b83340 100644
--- a/pkg/framework/plugins/nodeutilization/lownodeutilization_test.go
+++ b/pkg/framework/plugins/nodeutilization/lownodeutilization_test.go
@@ -58,6 +58,7 @@ func TestLowNodeUtilization(t *testing.T) {
 		pods                         []*v1.Pod
 		expectedPodsEvicted          uint
 		evictedPods                  []string
+		evictableNamespaces          *api.Namespaces
 	}{
 		{
 			name: "no evictable pods",
@@ -155,6 +156,130 @@ func TestLowNodeUtilization(t *testing.T) {
 			},
 			expectedPodsEvicted: 4,
 		},
+		{
+			name: "without priorities, but excluding namespaces",
+			thresholds: api.ResourceThresholds{
+				v1.ResourceCPU:  30,
+				v1.ResourcePods: 30,
+			},
+			targetThresholds: api.ResourceThresholds{
+				v1.ResourceCPU:  50,
+				v1.ResourcePods: 50,
+			},
+			nodes: []*v1.Node{
+				test.BuildTestNode(n1NodeName, 4000, 3000, 9, nil),
+				test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
+				test.BuildTestNode(n3NodeName, 4000, 3000, 10, test.SetNodeUnschedulable),
+			},
+			pods: []*v1.Pod{
+				test.BuildTestPod("p1", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace1"
+				}),
+				test.BuildTestPod("p2", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace1"
+				}),
+				test.BuildTestPod("p3", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace1"
+				}),
+				test.BuildTestPod("p4", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace1"
+				}),
+				test.BuildTestPod("p5", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace1"
+				}),
+				// These won't be evicted.
+				test.BuildTestPod("p6", 400, 0, n1NodeName, test.SetDSOwnerRef),
+				test.BuildTestPod("p7", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					// A pod with local storage.
+					test.SetNormalOwnerRef(pod)
+					pod.Spec.Volumes = []v1.Volume{
+						{
+							Name: "sample",
+							VolumeSource: v1.VolumeSource{
+								HostPath: &v1.HostPathVolumeSource{Path: "somePath"},
+								EmptyDir: &v1.EmptyDirVolumeSource{
+									SizeLimit: resource.NewQuantity(int64(10), resource.BinarySI)},
+							},
+						},
+					}
+					// A Mirror Pod.
+					pod.Annotations = test.GetMirrorPodAnnotation()
+				}),
+				test.BuildTestPod("p8", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					// A Critical Pod.
+					pod.Namespace = "kube-system"
+					priority := utils.SystemCriticalPriority
+					pod.Spec.Priority = &priority
+				}),
+				test.BuildTestPod("p9", 400, 0, n2NodeName, test.SetRSOwnerRef),
+			},
+			evictableNamespaces: &api.Namespaces{
+				Exclude: []string{
+					"namespace1",
+				},
+			},
+			expectedPodsEvicted: 0,
+		},
+		{
+			name: "without priorities, but include only default namespace",
+			thresholds: api.ResourceThresholds{
+				v1.ResourceCPU:  30,
+				v1.ResourcePods: 30,
+			},
+			targetThresholds: api.ResourceThresholds{
+				v1.ResourceCPU:  50,
+				v1.ResourcePods: 50,
+			},
+			nodes: []*v1.Node{
+				test.BuildTestNode(n1NodeName, 4000, 3000, 9, nil),
+				test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
+				test.BuildTestNode(n3NodeName, 4000, 3000, 10, test.SetNodeUnschedulable),
+			},
+			pods: []*v1.Pod{
+				test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
+				test.BuildTestPod("p2", 400, 0, n1NodeName, test.SetRSOwnerRef),
+				test.BuildTestPod("p3", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace3"
+				}),
+				test.BuildTestPod("p4", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace4"
+				}),
+				test.BuildTestPod("p5", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					pod.Namespace = "namespace5"
+				}),
+				// These won't be evicted.
+				test.BuildTestPod("p6", 400, 0, n1NodeName, test.SetDSOwnerRef),
+				test.BuildTestPod("p7", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					// A pod with local storage.
+					test.SetNormalOwnerRef(pod)
+					pod.Spec.Volumes = []v1.Volume{
+						{
+							Name: "sample",
+							VolumeSource: v1.VolumeSource{
+								HostPath: &v1.HostPathVolumeSource{Path: "somePath"},
+								EmptyDir: &v1.EmptyDirVolumeSource{
+									SizeLimit: resource.NewQuantity(int64(10), resource.BinarySI)},
+							},
+						},
+					}
+					// A Mirror Pod.
+					pod.Annotations = test.GetMirrorPodAnnotation()
+				}),
+				test.BuildTestPod("p8", 400, 0, n1NodeName, func(pod *v1.Pod) {
+					// A Critical Pod.
+					pod.Namespace = "kube-system"
+					priority := utils.SystemCriticalPriority
+					pod.Spec.Priority = &priority
+				}),
+				test.BuildTestPod("p9", 400, 0, n2NodeName, test.SetRSOwnerRef),
+			},
+			evictableNamespaces: &api.Namespaces{
+				Include: []string{
+					"default",
+				},
+			},
+			expectedPodsEvicted: 2,
+		},
 		{
 			name: "without priorities stop when cpu capacity is depleted",
 			thresholds: api.ResourceThresholds{
@@ -794,6 +919,7 @@ func TestLowNodeUtilization(t *testing.T) {
 				Thresholds:             test.thresholds,
 				TargetThresholds:       test.targetThresholds,
 				UseDeviationThresholds: test.useDeviationThresholds,
+				EvictableNamespaces:    test.evictableNamespaces,
 			},
 				handle)
 			if err != nil {