feat: add new on-demand allocation strategy

This commit adds a new on-demand allocation strategy: lowest-price.

Author: Fedosin

config/crd/bases/infrastructure.cluster.x-k8s.io_awsmachinepools.yaml

@@ -731,6 +731,7 @@ spec:
                           instance types to fulfill On-Demand capacity.
                         enum:
                         - prioritized
+                        - lowest-price
                         type: string
                       onDemandBaseCapacity:
                         default: 0

exp/api/v1beta2/types.go

@@ -137,6 +137,11 @@ var (
 	// OnDemandAllocationStrategyPrioritized uses the order of instance type overrides
 	// for the LaunchTemplate to define the launch priority of each instance type.
 	OnDemandAllocationStrategyPrioritized = OnDemandAllocationStrategy("prioritized")
+
+	// OnDemandAllocationStrategyLowestPrice will make the Auto Scaling group launch
+	// instances using the On-Demand pools with the lowest price, and evenly allocates
+	// your instances across the On-Demand pools that you specify.
+	OnDemandAllocationStrategyLowestPrice = OnDemandAllocationStrategy("lowest-price")
 )
 
 // SpotAllocationStrategy indicates how to allocate instances across Spot Instance pools.
@@ -165,7 +170,7 @@ var (
 
 // InstancesDistribution to configure distribution of On-Demand Instances and Spot Instances.
 type InstancesDistribution struct {
-	// +kubebuilder:validation:Enum=prioritized
+	// +kubebuilder:validation:Enum=prioritized;lowest-price
 	// +kubebuilder:default=prioritized
 	OnDemandAllocationStrategy OnDemandAllocationStrategy `json:"onDemandAllocationStrategy,omitempty"`
 

exp/controllers/awsmachinepool_controller_test.go

@@ -82,7 +82,20 @@ func TestAWSMachinePoolReconciler(t *testing.T) {
 			},
 			Spec: expinfrav1.AWSMachinePoolSpec{
 				MinSize: int32(0),
-				MaxSize: int32(1),
+				MaxSize: int32(100),
+				MixedInstancesPolicy: &expinfrav1.MixedInstancesPolicy{
+					InstancesDistribution: &expinfrav1.InstancesDistribution{
+						OnDemandAllocationStrategy:          expinfrav1.OnDemandAllocationStrategyPrioritized,
+						SpotAllocationStrategy:              expinfrav1.SpotAllocationStrategyCapacityOptimized,
+						OnDemandBaseCapacity:                aws.Int64(0),
+						OnDemandPercentageAboveBaseCapacity: aws.Int64(100),
+					},
+					Overrides: []expinfrav1.Overrides{
+						{
+							InstanceType: "m6a.32xlarge",
+						},
+					},
+				},
 			},
 		}
 
@@ -383,7 +396,20 @@ func TestAWSMachinePoolReconciler(t *testing.T) {
 
 			asg := expinfrav1.AutoScalingGroup{
 				MinSize: int32(0),
-				MaxSize: int32(1),
+				MaxSize: int32(100),
+				MixedInstancesPolicy: &expinfrav1.MixedInstancesPolicy{
+					InstancesDistribution: &expinfrav1.InstancesDistribution{
+						OnDemandAllocationStrategy:          expinfrav1.OnDemandAllocationStrategyPrioritized,
+						SpotAllocationStrategy:              expinfrav1.SpotAllocationStrategyCapacityOptimized,
+						OnDemandBaseCapacity:                aws.Int64(0),
+						OnDemandPercentageAboveBaseCapacity: aws.Int64(100),
+					},
+					Overrides: []expinfrav1.Overrides{
+						{
+							InstanceType: "m6a.32xlarge",
+						},
+					},
+				},
 				Subnets: []string{"subnet1", "subnet2"}}
 			ec2Svc.EXPECT().ReconcileLaunchTemplate(gomock.Any(), gomock.Any(), gomock.Any()).Return(nil)
 			ec2Svc.EXPECT().ReconcileTags(gomock.Any(), gomock.Any()).Return(nil)
@@ -401,7 +427,7 @@ func TestAWSMachinePoolReconciler(t *testing.T) {
 
 			asg := expinfrav1.AutoScalingGroup{
 				MinSize: int32(0),
-				MaxSize: int32(1),
+				MaxSize: int32(100),
 				Subnets: []string{"subnet1", "subnet2"}}
 			ec2Svc.EXPECT().ReconcileLaunchTemplate(gomock.Any(), gomock.Any(), gomock.Any()).Return(nil)
 			ec2Svc.EXPECT().ReconcileTags(gomock.Any(), gomock.Any()).Return(nil)

pkg/cloud/services/autoscaling/autoscalinggroup.go

@@ -65,8 +65,13 @@ func (s *Service) SDKToAutoScalingGroup(v *autoscaling.Group) (*expinfrav1.AutoS
 		}
 
 		onDemandAllocationStrategy := aws.StringValue(v.MixedInstancesPolicy.InstancesDistribution.OnDemandAllocationStrategy)
-		if onDemandAllocationStrategy == string(expinfrav1.OnDemandAllocationStrategyPrioritized) {
+		switch onDemandAllocationStrategy {
+		case string(expinfrav1.OnDemandAllocationStrategyPrioritized):
 			i.MixedInstancesPolicy.InstancesDistribution.OnDemandAllocationStrategy = expinfrav1.OnDemandAllocationStrategyPrioritized
+		case string(expinfrav1.OnDemandAllocationStrategyLowestPrice):
+			i.MixedInstancesPolicy.InstancesDistribution.OnDemandAllocationStrategy = expinfrav1.OnDemandAllocationStrategyLowestPrice
+		default:
+			return nil, fmt.Errorf("unsupported on-demand allocation strategy: %s", onDemandAllocationStrategy)
 		}
 
 		spotAllocationStrategy := aws.StringValue(v.MixedInstancesPolicy.InstancesDistribution.SpotAllocationStrategy)

pkg/cloud/services/autoscaling/autoscalinggroup_test.go

@@ -302,6 +302,34 @@ func TestServiceSDKToAutoScalingGroup(t *testing.T) {
 			},
 			wantErr: false,
 		},
+		{
+			name: "invalid input - incorrect on-demand allocation strategy",
+			input: &autoscaling.Group{
+				AutoScalingGroupARN:  aws.String("test-id"),
+				AutoScalingGroupName: aws.String("test-name"),
+				DesiredCapacity:      aws.Int64(1234),
+				MaxSize:              aws.Int64(1234),
+				MinSize:              aws.Int64(1234),
+				CapacityRebalance:    aws.Bool(true),
+				MixedInstancesPolicy: &autoscaling.MixedInstancesPolicy{
+					InstancesDistribution: &autoscaling.InstancesDistribution{
+						OnDemandAllocationStrategy:          aws.String("prioritized"),
+						OnDemandBaseCapacity:                aws.Int64(1234),
+						OnDemandPercentageAboveBaseCapacity: aws.Int64(1234),
+						SpotAllocationStrategy:              aws.String("INVALIDONDEMANDALLOCATIONSTRATEGY"),
+					},
+					LaunchTemplate: &autoscaling.LaunchTemplate{
+						Overrides: []*autoscaling.LaunchTemplateOverrides{
+							{
+								InstanceType:     aws.String("t2.medium"),
+								WeightedCapacity: aws.String("test-weighted-cap"),
+							},
+						},
+					},
+				},
+			},
+			wantErr: true,
+		},
 		{
 			name: "invalid input - incorrect spot allocation strategy",
 			input: &autoscaling.Group{