[Feature] Use image of Ray head container as the default Ray Autoscaler container

helm-chart/kuberay-operator/crds/ray.io_rayclusters.yaml

@@ -6074,8 +6074,8 @@ spec:
                   type: string
                 type: object
               rayVersion:
-                description: RayVersion is the version of ray being used. This determines
-                  the autoscaler's image version.
+                description: RayVersion is used to determine the command for the Kubernetes
+                  Job managed by RayJob
                 type: string
               workerGroupSpecs:
                 description: WorkerGroupSpecs are the specs for the worker pods

helm-chart/kuberay-operator/crds/ray.io_rayjobs.yaml

@@ -6342,8 +6342,8 @@ spec:
                       type: string
                     type: object
                   rayVersion:
-                    description: RayVersion is the version of ray being used. This
-                      determines the autoscaler's image version.
+                    description: RayVersion is used to determine the command for the
+                      Kubernetes Job managed by RayJob
                     type: string
                   workerGroupSpecs:
                     description: WorkerGroupSpecs are the specs for the worker pods

helm-chart/kuberay-operator/crds/ray.io_rayservices.yaml

@@ -6316,8 +6316,8 @@ spec:
                       type: string
                     type: object
                   rayVersion:
-                    description: RayVersion is the version of ray being used. This
-                      determines the autoscaler's image version.
+                    description: RayVersion is used to determine the command for the
+                      Kubernetes Job managed by RayJob
                     type: string
                   workerGroupSpecs:
                     description: WorkerGroupSpecs are the specs for the worker pods

ray-operator/apis/ray/v1alpha1/raycluster_types.go

@@ -16,7 +16,7 @@ type RayClusterSpec struct {
 	HeadGroupSpec HeadGroupSpec `json:"headGroupSpec"`
 	// WorkerGroupSpecs are the specs for the worker pods
 	WorkerGroupSpecs []WorkerGroupSpec `json:"workerGroupSpecs,omitempty"`
-	// RayVersion is the version of ray being used. This determines the autoscaler's image version.
+	// RayVersion is used to determine the command for the Kubernetes Job managed by RayJob
 	RayVersion string `json:"rayVersion,omitempty"`
 	// EnableInTreeAutoscaling indicates whether operator should create in tree autoscaling configs
 	EnableInTreeAutoscaling *bool `json:"enableInTreeAutoscaling,omitempty"`
@@ -86,12 +86,13 @@ type AutoscalerOptions struct {
 	// More info: https://kubernetes.io/docs/tasks/configure-pod-container/security-context/
 	SecurityContext *v1.SecurityContext `json:"securityContext,omitempty"`
 	// IdleTimeoutSeconds is the number of seconds to wait before scaling down a worker pod which is not using Ray resources.
-	// Defaults to 60 (one minute).
+	// Defaults to 60 (one minute). It is not read by the KubeRay operator but by the Ray autoscaler.
 	IdleTimeoutSeconds *int32 `json:"idleTimeoutSeconds,omitempty"`
 	// UpscalingMode is "Conservative", "Default", or "Aggressive."
 	// Conservative: Upscaling is rate-limited; the number of pending worker pods is at most the size of the Ray cluster.
 	// Default: Upscaling is not rate-limited.
 	// Aggressive: An alias for Default; upscaling is not rate-limited.
+	// It is not read by the KubeRay operator but by the Ray autoscaler.
 	UpscalingMode *UpscalingMode `json:"upscalingMode,omitempty"`
 }
 

ray-operator/apis/ray/v1alpha1/raycluster_types_test.go

@@ -15,7 +15,6 @@ var myRayCluster = &RayCluster{
 		Namespace: "default",
 	},
 	Spec: RayClusterSpec{
-		RayVersion: "1.0",
 		HeadGroupSpec: HeadGroupSpec{
 			Replicas: pointer.Int32Ptr(1),
 			RayStartParams: map[string]string{

ray-operator/apis/ray/v1alpha1/rayservice_types_test.go

@@ -70,7 +70,6 @@ var myRayService = &RayService{
 			},
 		},
 		RayClusterSpec: RayClusterSpec{
-			RayVersion: "1.12.1",
 			HeadGroupSpec: HeadGroupSpec{
 				Replicas: pointer.Int32Ptr(1),
 				RayStartParams: map[string]string{
@@ -355,8 +354,7 @@ var expected = `{
 
                }
             }
-         ],
-         "rayVersion":"1.12.1"
+         ]
       }
    },
    "status":{

ray-operator/config/crd/bases/ray.io_rayclusters.yaml

@@ -6074,8 +6074,8 @@ spec:
                   type: string
                 type: object
               rayVersion:
-                description: RayVersion is the version of ray being used. This determines
-                  the autoscaler's image version.
+                description: RayVersion is used to determine the command for the Kubernetes
+                  Job managed by RayJob
                 type: string
               workerGroupSpecs:
                 description: WorkerGroupSpecs are the specs for the worker pods

ray-operator/config/crd/bases/ray.io_rayjobs.yaml

@@ -6342,8 +6342,8 @@ spec:
                       type: string
                     type: object
                   rayVersion:
-                    description: RayVersion is the version of ray being used. This
-                      determines the autoscaler's image version.
+                    description: RayVersion is used to determine the command for the
+                      Kubernetes Job managed by RayJob
                     type: string
                   workerGroupSpecs:
                     description: WorkerGroupSpecs are the specs for the worker pods

ray-operator/config/crd/bases/ray.io_rayservices.yaml

@@ -6316,8 +6316,8 @@ spec:
                       type: string
                     type: object
                   rayVersion:
-                    description: RayVersion is the version of ray being used. This
-                      determines the autoscaler's image version.
+                    description: RayVersion is used to determine the command for the
+                      Kubernetes Job managed by RayJob
                     type: string
                   workerGroupSpecs:
                     description: WorkerGroupSpecs are the specs for the worker pods

ray-operator/controllers/ray/common/ingress_test.go

@@ -24,7 +24,6 @@ var instanceWithIngressEnabled = &rayv1alpha1.RayCluster{
 		},
 	},
 	Spec: rayv1alpha1.RayClusterSpec{
-		RayVersion: "1.0",
 		HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 			Replicas: pointer.Int32Ptr(1),
 			Template: corev1.PodTemplateSpec{
@@ -49,7 +48,6 @@ var instanceWithIngressEnabledWithoutIngressClass = &rayv1alpha1.RayCluster{
 		Namespace: "default",
 	},
 	Spec: rayv1alpha1.RayClusterSpec{
-		RayVersion: "1.0",
 		HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 			Replicas: pointer.Int32Ptr(1),
 			Template: corev1.PodTemplateSpec{

ray-operator/controllers/ray/common/pod.go

@@ -115,9 +115,8 @@ func DefaultHeadPodTemplate(instance rayv1alpha1.RayCluster, headSpec rayv1alpha
 		// set custom service account with proper roles bound.
 		// utils.CheckName clips the name to match the behavior of reconcileAutoscalerServiceAccount
 		podTemplate.Spec.ServiceAccountName = utils.CheckName(utils.GetHeadGroupServiceAccountName(&instance))
-		rayHeadImage := podTemplate.Spec.Containers[RayContainerIndex].Image
-		// Determine the default image to use for the Ray container.
-		autoscalerImage := getAutoscalerImage(rayHeadImage, instance.Spec.RayVersion)
+		// Use the same image as Ray head container by default.
+		autoscalerImage := podTemplate.Spec.Containers[RayContainerIndex].Image
 		// inject autoscaler container into head pod
 		autoscalerContainer := BuildAutoscalerContainer(autoscalerImage)
 		// Merge the user overrides from autoscalerOptions into the autoscaler container config.
@@ -138,44 +137,6 @@ func DefaultHeadPodTemplate(instance rayv1alpha1.RayCluster, headSpec rayv1alpha
 	return podTemplate
 }
 
-// getAutoscalerImage determines the default autoscaler image
-func getAutoscalerImage(rayHeadImage string, rayVersion string) string {
-	if autoscalerSupportIsStable(rayVersion) {
-		// For Ray versions >= 2.0.0, use the Ray head's image to run the autoscaler.
-		return rayHeadImage
-	} else {
-		// For older Ray versions, use the Ray 2.0.0 image to run the autoscaler.
-		return FallbackDefaultAutoscalerImage
-	}
-}
-
-// Determine if autoscaler support is stable in the given rayVersion.
-// Return false exactly when the major version is successfully parsed and less than 2.
-// Example rayVersion inputs that return true: "2.0.0", "2.0", "2", "2.0.0rc1", "nightly", "latest", "unknown".
-// Example inputs that return false: "1.13.0", "1.12", "1".
-func autoscalerSupportIsStable(rayVersion string) bool {
-	// Try to determine major version by extracting everything that comes before the first "."
-	firstDotIndex := strings.Index(rayVersion, ".")
-	var majorVersionString string
-	if firstDotIndex == -1 {
-		// If there is no ".", try parsing the entire rayVersion as the major version.
-		majorVersionString = rayVersion
-	} else {
-		// Everything up to the first "."
-		majorVersionString = rayVersion[:firstDotIndex]
-	}
-
-	if majorVersion, err := strconv.Atoi(majorVersionString); err == nil {
-		return majorVersion >= 2
-	} else {
-		// If in doubt, just assume that the Ray version is >= 2.0.0,
-		// so that we use the Ray image to run the autoscaler.
-		// Currently, there is a lot of "doubt," since the version string is not validated.
-		// Users can always override the operator's choice of image with autoscalerOptions.image.
-		return true
-	}
-}
-
 func getEnableInitContainerInjection() bool {
 	if s := os.Getenv(EnableInitContainerInjectionEnvKey); strings.ToLower(s) == "false" {
 		return false

ray-operator/controllers/ray/common/pod_test.go

@@ -29,7 +29,6 @@ var instance = rayv1alpha1.RayCluster{
 		Namespace: "default",
 	},
 	Spec: rayv1alpha1.RayClusterSpec{
-		RayVersion: "2.0.0",
 		HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 			Replicas: pointer.Int32Ptr(1),
 			RayStartParams: map[string]string{
@@ -281,31 +280,6 @@ func TestAddEmptyDirVolumes(t *testing.T) {
 	assert.Equal(t, len(testPod.Spec.Volumes), 2)
 }
 
-func TestGetAutoscalerImage(t *testing.T) {
-	// rayVersion strings for which we judge autoscaler support is stable and thus
-	// use the same image for the autoscaler as for the Ray container.
-	newRayVersions := []string{"2.0.0", "2.0.0rc0", "2.0", "2", "latest", "nightly", "what's this"}
-	rayImage := "repo/image:tag"
-	for _, rayVersion := range newRayVersions {
-		expectedAutoscalerImage := rayImage
-		actualAutoscalerImage := getAutoscalerImage(rayImage, rayVersion)
-		if actualAutoscalerImage != expectedAutoscalerImage {
-			t.Fatalf("Expected `%v` but got `%v`", expectedAutoscalerImage, actualAutoscalerImage)
-		}
-	}
-
-	// rayVersion strings for which we judge autoscaler support is not stable and thus
-	// use the default Ray 2.0.0 image to run the autoscaler.
-	oldRayVersions := []string{"1", "1.13", "1.13.0"}
-	for _, rayVersion := range oldRayVersions {
-		expectedAutoscalerImage := "rayproject/ray:2.0.0"
-		actualAutoscalerImage := getAutoscalerImage(rayImage, rayVersion)
-		if actualAutoscalerImage != expectedAutoscalerImage {
-			t.Fatalf("Expected `%v` but got `%v`", expectedAutoscalerImage, actualAutoscalerImage)
-		}
-	}
-}
-
 func TestGetHeadPort(t *testing.T) {
 	headStartParams := make(map[string]string)
 	actualResult := GetHeadPort(headStartParams)
@@ -683,6 +657,34 @@ func TestHeadPodTemplate_WithAutoscalingEnabled(t *testing.T) {
 	}
 }
 
+func TestHeadPodTemplate_AutoscalerImage(t *testing.T) {
+	cluster := instance.DeepCopy()
+	cluster.Spec.EnableInTreeAutoscaling = &trueFlag
+	cluster.Spec.AutoscalerOptions = nil
+	podName := strings.ToLower(cluster.Name + DashSymbol + string(rayv1alpha1.HeadNode) + DashSymbol + utils.FormatInt32(0))
+
+	// Case 1: If `AutoscalerOptions.Image` is not set, the Autoscaler container should use the Ray head container's image by default.
+	expectedAutoscalerImage := cluster.Spec.HeadGroupSpec.Template.Spec.Containers[RayContainerIndex].Image
+	podTemplateSpec := DefaultHeadPodTemplate(*cluster, cluster.Spec.HeadGroupSpec, podName, "6379")
+	pod := v1.Pod{
+		Spec: podTemplateSpec.Spec,
+	}
+	autoscalerContainerIndex := getAutoscalerContainerIndex(pod)
+	assert.Equal(t, expectedAutoscalerImage, podTemplateSpec.Spec.Containers[autoscalerContainerIndex].Image)
+
+	// Case 2: If `AutoscalerOptions.Image` is set, the Autoscaler container should use the specified image.
+	customAutoscalerImage := "custom-autoscaler-xxx"
+	cluster = instance.DeepCopy()
+	cluster.Spec.EnableInTreeAutoscaling = &trueFlag
+	cluster.Spec.AutoscalerOptions = &rayv1alpha1.AutoscalerOptions{
+		Image: &customAutoscalerImage,
+	}
+	podTemplateSpec = DefaultHeadPodTemplate(*cluster, cluster.Spec.HeadGroupSpec, podName, "6379")
+	pod.Spec = podTemplateSpec.Spec
+	autoscalerContainerIndex = getAutoscalerContainerIndex(pod)
+	assert.Equal(t, customAutoscalerImage, podTemplateSpec.Spec.Containers[autoscalerContainerIndex].Image)
+}
+
 // If no service account is specified in the RayCluster,
 // the head pod's service account should be an empty string.
 func TestHeadPodTemplate_WithNoServiceAccount(t *testing.T) {

ray-operator/controllers/ray/common/route_test.go

@@ -21,7 +21,6 @@ var instanceWithRouteEnabled = &rayv1alpha1.RayCluster{
 		},
 	},
 	Spec: rayv1alpha1.RayClusterSpec{
-		RayVersion: "1.0",
 		HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 			Replicas:      pointer.Int32Ptr(1),
 			EnableIngress: pointer.BoolPtr(true),

ray-operator/controllers/ray/common/service_test.go

@@ -27,7 +27,6 @@ var (
 		},
 		Spec: rayv1alpha1.RayServiceSpec{
 			RayClusterSpec: rayv1alpha1.RayClusterSpec{
-				RayVersion: "1.0",
 				HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 					ServiceType: corev1.ServiceTypeClusterIP,
 				},
@@ -40,7 +39,6 @@ var (
 			Namespace: "default",
 		},
 		Spec: rayv1alpha1.RayClusterSpec{
-			RayVersion: "1.0",
 			HeadServiceAnnotations: map[string]string{
 				headServiceAnnotationKey1: headServiceAnnotationValue1,
 				headServiceAnnotationKey2: headServiceAnnotationValue2,

ray-operator/controllers/ray/raycluster_controller_fake_test.go

@@ -286,7 +286,6 @@ func setupTest(t *testing.T) {
 			Namespace: namespaceStr,
 		},
 		Spec: rayv1alpha1.RayClusterSpec{
-			RayVersion:              "1.0",
 			EnableInTreeAutoscaling: &enableInTreeAutoscaling,
 			HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 				Replicas: pointer.Int32Ptr(1),

ray-operator/controllers/ray/raycluster_controller_test.go

@@ -51,7 +51,6 @@ var _ = Context("Inside the default namespace", func() {
 			Namespace: "default",
 		},
 		Spec: rayv1alpha1.RayClusterSpec{
-			RayVersion:              "1.0",
 			EnableInTreeAutoscaling: &enableInTreeAutoscaling,
 			HeadGroupSpec: rayv1alpha1.HeadGroupSpec{
 				RayStartParams: map[string]string{