feat(api): add fractional GPU group type

.changes/unreleased/added-20260810-112001.yaml

@@ -0,0 +1,3 @@
+kind: Added
+body: |-
+  Add typed fractional GPU group API

deployments/kai-scheduler/crds/scheduling.run.ai_bindrequests.yaml

@@ -1329,10 +1329,23 @@ spec:
                       type: string
                   type: object
                 type: array
+              selectedFractionalGpuGroups:
+                description: |-
+                  SelectedFractionalGpuGroups is the selected GPU groups for fractional GPU resources.
+                  Only if the RecievedResourceType is "Fraction"
+                items:
+                  properties:
+                    computeSharingMode:
+                      type: string
+                    id:
+                      type: string
+                  type: object
+                type: array
               selectedGPUGroups:
                 description: |-
                   SelectedGPUGroups is the name of the selected GPU groups for fractional GPU resources.
                   Only if the RecievedResourceType is "Fraction"
+                  Deprecated: Use SelectedFractionalGpuGroups instead
                 items:
                   type: string
                 type: array

pkg/apis/scheduling/v1alpha2/bindrequest_types.go

@@ -25,8 +25,13 @@ type BindRequestSpec struct {
 
 	// SelectedGPUGroups is the name of the selected GPU groups for fractional GPU resources.
 	// Only if the RecievedResourceType is "Fraction"
+	// Deprecated: Use SelectedFractionalGpuGroups instead
 	SelectedGPUGroups []string `json:"selectedGPUGroups,omitempty"`
 
+	// SelectedFractionalGpuGroups is the selected GPU groups for fractional GPU resources.
+	// Only if the RecievedResourceType is "Fraction"
+	SelectedFractionalGpuGroups []FractionalGpuGroup `json:"selectedFractionalGpuGroups,omitempty"`
+
 	// ResourceClaims is the list of resource claims that need to be bound for this pod
 	ResourceClaimAllocations []ResourceClaimAllocation `json:"resourceClaimAllocations,omitempty"`
 
@@ -42,6 +47,70 @@ type BindRequestSpec struct {
 	BackoffLimit *int32 `json:"backoffLimit,omitempty"`
 }
 
+type GPUComputeSharingMode string
+
+const (
+	GPUComputeSharingModeTimeSlicing GPUComputeSharingMode = "time-slicing"
+	GPUComputeSharingModeSMSharing   GPUComputeSharingMode = "sm-sharing"
+)
+
+type FractionalGpuGroup struct {
+	ID                 string                `json:"id,omitempty"`
+	ComputeSharingMode GPUComputeSharingMode `json:"computeSharingMode,omitempty"`
+}
+
+func (group FractionalGpuGroup) WithDefaults() FractionalGpuGroup {
+	if group.ComputeSharingMode == "" {
+		group.ComputeSharingMode = GPUComputeSharingModeTimeSlicing
+	}
+	return group
+}
+
+func NewFractionalGpuGroups(gpuGroups []string, mode GPUComputeSharingMode) []FractionalGpuGroup {
+	if len(gpuGroups) == 0 {
+		return nil
+	}
+	mode = DefaultGPUComputeSharingMode(mode)
+	fractionalGpuGroups := make([]FractionalGpuGroup, 0, len(gpuGroups))
+	for _, gpuGroup := range gpuGroups {
+		fractionalGpuGroups = append(fractionalGpuGroups, FractionalGpuGroup{
+			ID:                 gpuGroup,
+			ComputeSharingMode: mode,
+		})
+	}
+	return fractionalGpuGroups
+}
+
+func DefaultGPUComputeSharingMode(mode GPUComputeSharingMode) GPUComputeSharingMode {
+	if mode == "" {
+		return GPUComputeSharingModeTimeSlicing
+	}
+	return mode
+}
+
+func (spec *BindRequestSpec) SelectedFractionalGpuGroupsOrDefault() []FractionalGpuGroup {
+	if len(spec.SelectedFractionalGpuGroups) > 0 {
+		fractionalGpuGroups := make([]FractionalGpuGroup, 0, len(spec.SelectedFractionalGpuGroups))
+		for _, fractionalGpuGroup := range spec.SelectedFractionalGpuGroups {
+			fractionalGpuGroups = append(fractionalGpuGroups, fractionalGpuGroup.WithDefaults())
+		}
+		return fractionalGpuGroups
+	}
+	return NewFractionalGpuGroups(spec.SelectedGPUGroups, GPUComputeSharingModeTimeSlicing)
+}
+
+func (spec *BindRequestSpec) SelectedFractionalGpuGroupIDs() []string {
+	fractionalGpuGroups := spec.SelectedFractionalGpuGroupsOrDefault()
+	if len(fractionalGpuGroups) == 0 {
+		return nil
+	}
+	gpuGroups := make([]string, 0, len(fractionalGpuGroups))
+	for _, fractionalGpuGroup := range fractionalGpuGroups {
+		gpuGroups = append(gpuGroups, fractionalGpuGroup.ID)
+	}
+	return gpuGroups
+}
+
 type ReceivedGPU struct {
 	// Count is the amount of GPUs devices that were received
 	Count int `json:"count,omitempty"`

pkg/common/constants/constants.go

@@ -21,6 +21,7 @@ const (
 	DefaultSchedulerName                  = "kai-scheduler"
 	DefaultKAINamespace                   = "kai-scheduler"
 	DefaultResourceReservationName        = "kai-resource-reservation"
+	GPUReservationPodPrefix               = "gpu-reservation"
 	DefaultScaleAdjustName                = "kai-scale-adjust"
 	DefaultKAIConfigSingeltonInstanceName = "kai-config"
 	DefaultNodePoolLabelKey               = "kai.scheduler/node-pool"
@@ -55,6 +56,7 @@ const (
 	SkipPodGrouperAnnotation      = "kai.scheduler/skip-podgrouper"
 	GpuFraction                   = "gpu-fraction"
 	GpuFractionContainerName      = "gpu-fraction-container-name"
+	GpuComputeSharingMode         = "kai.scheduler/gpu-compute-sharing-mode"
 	GpuMemory                     = "gpu-memory"
 	ReceivedResourceType          = "received-resource-type"
 	GpuFractionsNumDevices        = "gpu-fraction-num-devices"