LowNodeUtilization: fall back to the list of protected namespaces as excluded when a list of included namespace is specified

LowNodeUtilization does not support namespace inclusion. Thus, the list
of excluded namespace needs to fall back to the list of protected
namespace instead of not setting ommiting the namespace inclusion.

Author: ingvagabund

pkg/operator/target_config_reconciler.go

@@ -558,7 +558,7 @@ func softTopologyAndDuplicatesProfile(profileCustomizations *deschedulerv1.Profi
 	return profile, err
 }
 
-func lifecycleAndUtilizationProfile(profileCustomizations *deschedulerv1.ProfileCustomizations, includedNamespaces, excludedNamespaces []string, ignorePVCPods, evictLocalStoragePods bool) (*v1alpha2.DeschedulerProfile, error) {
+func lifecycleAndUtilizationProfile(profileCustomizations *deschedulerv1.ProfileCustomizations, includedNamespaces, excludedNamespaces, protectedNamespaces []string, ignorePVCPods, evictLocalStoragePods bool) (*v1alpha2.DeschedulerProfile, error) {
 	profile := &v1alpha2.DeschedulerProfile{
 		Name: string(deschedulerv1.LifecycleAndUtilization),
 		PluginConfigs: []v1alpha2.PluginConfig{
@@ -630,7 +630,12 @@ func lifecycleAndUtilizationProfile(profileCustomizations *deschedulerv1.Profile
 		}
 		if len(includedNamespaces) > 0 {
 			// log a warning if user tries to enable ns inclusion with a profile that activates LowNodeUtilization
-			klog.Warning("LowNodeUtilization is enabled, however it does not support namespace inclusion. Namespace inclusion will only be considered by other strategies (like RemovePodsHavingTooManyRestarts and PodLifeTime)")
+			klog.Warning("LowNodeUtilization is enabled, however it does not support namespace inclusion. Namespace inclusion will only be considered by other strategies (like RemovePodsHavingTooManyRestarts and PodLifeTime). Falling back to a list of excluded protected namespaces.")
+			if len(excludedNamespaces) == 0 {
+				profile.PluginConfigs[2].Args.Object.(*nodeutilization.LowNodeUtilizationArgs).EvictableNamespaces = &deschedulerapi.Namespaces{
+					Exclude: protectedNamespaces,
+				}
+			}
 		}
 		if len(excludedNamespaces) > 0 {
 			profile.PluginConfigs[2].Args.Object.(*nodeutilization.LowNodeUtilizationArgs).EvictableNamespaces = &deschedulerapi.Namespaces{
@@ -703,8 +708,8 @@ func lifecycleAndUtilizationProfile(profileCustomizations *deschedulerv1.Profile
 	return profile, nil
 }
 
-func longLifecycleProfile(profileCustomizations *deschedulerv1.ProfileCustomizations, includedNamespaces, excludedNamespaces []string, ignorePVCPods, evictLocalStoragePods bool) (*v1alpha2.DeschedulerProfile, error) {
-	profile, err := lifecycleAndUtilizationProfile(profileCustomizations, includedNamespaces, excludedNamespaces, ignorePVCPods, evictLocalStoragePods)
+func longLifecycleProfile(profileCustomizations *deschedulerv1.ProfileCustomizations, includedNamespaces, excludedNamespaces, protectedNamespaces []string, ignorePVCPods, evictLocalStoragePods bool) (*v1alpha2.DeschedulerProfile, error) {
+	profile, err := lifecycleAndUtilizationProfile(profileCustomizations, includedNamespaces, excludedNamespaces, protectedNamespaces, ignorePVCPods, evictLocalStoragePods)
 	if err != nil {
 		return profile, err
 	}
@@ -907,11 +912,11 @@ func (c *TargetConfigReconciler) manageConfigMap(descheduler *deschedulerv1.Kube
 		case deschedulerv1.SoftTopologyAndDuplicates:
 			profile, err = softTopologyAndDuplicatesProfile(descheduler.Spec.ProfileCustomizations, includedNamespaces, excludedNamespaces, ignorePVCPods, evictLocalStoragePods)
 		case deschedulerv1.LifecycleAndUtilization:
-			profile, err = lifecycleAndUtilizationProfile(descheduler.Spec.ProfileCustomizations, includedNamespaces, excludedNamespaces, ignorePVCPods, evictLocalStoragePods)
+			profile, err = lifecycleAndUtilizationProfile(descheduler.Spec.ProfileCustomizations, includedNamespaces, excludedNamespaces, c.protectedNamespaces, ignorePVCPods, evictLocalStoragePods)
 		case deschedulerv1.EvictPodsWithLocalStorage, deschedulerv1.EvictPodsWithPVC:
 			continue
 		case deschedulerv1.DevPreviewLongLifecycle, deschedulerv1.LongLifecycle:
-			profile, err = longLifecycleProfile(descheduler.Spec.ProfileCustomizations, includedNamespaces, excludedNamespaces, ignorePVCPods, evictLocalStoragePods)
+			profile, err = longLifecycleProfile(descheduler.Spec.ProfileCustomizations, includedNamespaces, excludedNamespaces, c.protectedNamespaces, ignorePVCPods, evictLocalStoragePods)
 		case deschedulerv1.CompactAndScale:
 			profile, err = compactAndScaleProfile(descheduler.Spec.ProfileCustomizations, includedNamespaces, excludedNamespaces, ignorePVCPods, evictLocalStoragePods)
 		default:

pkg/operator/target_config_reconciler_test.go

@@ -127,6 +127,24 @@ func TestManageConfigMap(t *testing.T) {
 			},
 			err: fmt.Errorf("It is invalid to set both .spec.profileCustomizations.thresholdPriority and .spec.profileCustomizations.ThresholdPriorityClassName fields"),
 		},
+		{
+			name: "LowNodeUtilizationIncludedNamespace",
+			descheduler: &deschedulerv1.KubeDescheduler{
+				Spec: deschedulerv1.KubeDeschedulerSpec{
+					Profiles: []deschedulerv1.DeschedulerProfile{"LifecycleAndUtilization"},
+					ProfileCustomizations: &deschedulerv1.ProfileCustomizations{
+						DevLowNodeUtilizationThresholds: &deschedulerv1.LowThreshold,
+						Namespaces: deschedulerv1.Namespaces{
+							Included: []string{"includedNamespace"},
+						},
+					},
+				},
+			},
+			want: &corev1.ConfigMap{
+				TypeMeta: metav1.TypeMeta{APIVersion: "v1", Kind: "ConfigMap"},
+				Data:     map[string]string{"policy.yaml": string(bindata.MustAsset("assets/lowNodeUtilizationIncludedNamespace.yaml"))},
+			},
+		},
 		{
 			name: "LowNodeUtilizationLow",
 			descheduler: &deschedulerv1.KubeDescheduler{

pkg/operator/testdata/assets/longLifecycleWithNamespaces.yaml

@@ -12,6 +12,12 @@ profiles:
       podRestartThreshold: 100
     name: RemovePodsHavingTooManyRestarts
   - args:
+      evictableNamespaces:
+        exclude:
+        - kube-system
+        - hypershift
+        - openshift
+        - openshift-kube-scheduler
       metricsUtilization:
         prometheus: {}
       targetThresholds:

pkg/operator/testdata/assets/lowNodeUtilizationIncludedNamespace.yaml

@@ -0,0 +1,66 @@
+apiVersion: descheduler/v1alpha2
+kind: DeschedulerPolicy
+metricsCollector: {}
+profiles:
+- name: LifecycleAndUtilization
+  pluginConfig:
+  - args:
+      maxPodLifeTimeSeconds: 86400
+      namespaces:
+        include:
+        - includedNamespace
+    name: PodLifeTime
+  - args:
+      includingInitContainers: true
+      namespaces:
+        include:
+        - includedNamespace
+      podRestartThreshold: 100
+    name: RemovePodsHavingTooManyRestarts
+  - args:
+      evictableNamespaces:
+        exclude:
+        - kube-system
+        - hypershift
+        - openshift
+        - openshift-kube-scheduler
+      metricsUtilization:
+        prometheus: {}
+      targetThresholds:
+        cpu: 30
+        memory: 30
+        pods: 30
+      thresholds:
+        cpu: 10
+        memory: 10
+        pods: 10
+    name: LowNodeUtilization
+  - args:
+      ignorePvcPods: true
+    name: DefaultEvictor
+  plugins:
+    balance:
+      disabled: null
+      enabled:
+      - LowNodeUtilization
+    deschedule:
+      disabled: null
+      enabled:
+      - PodLifeTime
+      - RemovePodsHavingTooManyRestarts
+    filter:
+      disabled: null
+      enabled:
+      - DefaultEvictor
+    preevictionfilter:
+      disabled: null
+      enabled: null
+    presort:
+      disabled: null
+      enabled: null
+    sort:
+      disabled: null
+      enabled: null
+prometheus:
+  authToken:
+    secretReference: {}