feat(autoscaling): support default instance warmup for Auto Scaling groups

packages/@aws-cdk/aws-autoscaling/README.md

@@ -295,15 +295,15 @@ const autoScalingGroup = new autoscaling.AutoScalingGroup(this, 'ASG', {
   vpc,
   instanceType,
   machineImage,
-  blockDevices: [{
+  blockDevices: [
     {
         deviceName: 'gp3-volume',
         volume: autoscaling.BlockDeviceVolume.ebs(15, {
           volumeType: autoscaling.EbsDeviceVolumeType.GP3,
           throughput: 125,
         }),
       },
-  }],
+  ],
   // ...
 });
 ```
@@ -574,6 +574,35 @@ autoScalingGroup.addWarmPool({
 });
 ```
 
+### Default Instance Warming
+
+You can use the default instance warmup feature to improve the Amazon CloudWatch metrics used for dynamic scaling. 
+When default instance warmup is not enabled, each instance starts contributing usage data to the aggregated metrics 
+as soon as the instance reaches the InService state. However, if you enable default instance warmup, this lets 
+your instances finish warming up before they contribute the usage data.
+
+To optimize the performance of scaling policies that scale continuously, such as target tracking and step scaling 
+policies, we strongly recommend that you enable the default instance warmup, even if its value is set to 0 seconds. 
+
+To set up Default Instance Warming for an autoscaling group, simply pass it in as a prop
+
+```ts
+declare const vpc: ec2.Vpc;
+declare const instanceType: ec2.InstanceType;
+declare const machineImage: ec2.IMachineImage;
+
+
+new autoscaling.AutoScalingGroup(this, 'ASG', {
+  vpc,
+  instanceType,
+  machineImage,
+
+  // ...
+
+  defaultInstanceWarmup: Duration.seconds(5),
+});
+```
+
 ## Future work
 
 * [ ] CloudWatch Events (impossible to add currently as the AutoScalingGroup ARN is

packages/@aws-cdk/aws-autoscaling/lib/auto-scaling-group.ts

@@ -336,6 +336,23 @@ export interface CommonAutoScalingGroupProps {
    * @default - `TerminationPolicy.DEFAULT`
    */
   readonly terminationPolicies?: TerminationPolicy[];
+
+  /**
+   * The amount of time, in seconds, until a newly launched instance can contribute to the Amazon CloudWatch metrics.
+   * This delay lets an instance finish initializing before Amazon EC2 Auto Scaling aggregates instance metrics,
+   * resulting in more reliable usage data. Set this value equal to the amount of time that it takes for resource
+   * consumption to become stable after an instance reaches the InService state.
+   *
+   * To optimize the performance of scaling policies that scale continuously, such as target tracking and
+   * step scaling policies, we strongly recommend that you enable the default instance warmup, even if its value is set to 0 seconds
+   *
+   * Default instance warmup will not be added if no value is specified
+   *
+   * @see https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-default-instance-warmup.html
+   *
+   * @default None
+   */
+  readonly defaultInstanceWarmup?: Duration;
 }
 
 /**
@@ -1344,6 +1361,7 @@ export class AutoScalingGroup extends AutoScalingGroupBase implements
       maxInstanceLifetime: this.maxInstanceLifetime ? this.maxInstanceLifetime.toSeconds() : undefined,
       newInstancesProtectedFromScaleIn: Lazy.any({ produce: () => this.newInstancesProtectedFromScaleIn }),
       terminationPolicies: props.terminationPolicies,
+      defaultInstanceWarmup: props.defaultInstanceWarmup?.toSeconds(),
       ...this.getLaunchSettings(launchConfig, props.launchTemplate, props.mixedInstancesPolicy),
     };
 

packages/@aws-cdk/aws-autoscaling/test/auto-scaling-group.test.ts

@@ -286,6 +286,25 @@ describe('auto scaling group', () => {
     });
   });
 
+  test('can specify only defaultInstanceWarmup', () => {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = mockVpc(stack);
+
+    // WHEN
+    new autoscaling.AutoScalingGroup(stack, 'MyFleet', {
+      instanceType: ec2.InstanceType.of(ec2.InstanceClass.M4, ec2.InstanceSize.MICRO),
+      machineImage: new ec2.AmazonLinuxImage(),
+      vpc,
+      defaultInstanceWarmup: cdk.Duration.seconds(5),
+    });
+
+    // THEN
+    Template.fromStack(stack).hasResourceProperties('AWS::AutoScaling::AutoScalingGroup', {
+      DefaultInstanceWarmup: 5,
+    });
+  });
+
   test('addToRolePolicy can be used to add statements to the role policy', () => {
     const stack = new cdk.Stack(undefined, 'MyStack', { env: { region: 'us-east-1', account: '1234' } });
     const vpc = mockVpc(stack);

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.js.snapshot/aws-cdk-asg-integ.assets.json

@@ -1,15 +1,15 @@
 {
-  "version": "21.0.0",
+  "version": "22.0.0",
   "files": {
-    "2ca8f144c3e288148d58c9b9e86c9034f6a72b09cecffac3a5d406f8f53d5b18": {
+    "768b8ff8b1178a04dbfca488da9459f4f402bfad643db0b4791787ef23ec4db5": {
       "source": {
         "path": "aws-cdk-asg-integ.template.json",
         "packaging": "file"
       },
       "destinations": {
         "current_account-current_region": {
           "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
-          "objectKey": "2ca8f144c3e288148d58c9b9e86c9034f6a72b09cecffac3a5d406f8f53d5b18.json",
+          "objectKey": "768b8ff8b1178a04dbfca488da9459f4f402bfad643db0b4791787ef23ec4db5.json",
           "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
         }
       }

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.js.snapshot/aws-cdk-asg-integ.template.json

@@ -507,6 +507,38 @@
     }
    }
   },
+  "AsgWithDefaultInstanceWarmupASG7A481C66": {
+   "Type": "AWS::AutoScaling::AutoScalingGroup",
+   "Properties": {
+    "MaxSize": "1",
+    "MinSize": "1",
+    "DefaultInstanceWarmup": 5,
+    "LaunchTemplate": {
+     "LaunchTemplateId": {
+      "Ref": "MainLT4FC09097"
+     },
+     "Version": {
+      "Fn::GetAtt": [
+       "MainLT4FC09097",
+       "LatestVersionNumber"
+      ]
+     }
+    },
+    "VPCZoneIdentifier": [
+     {
+      "Ref": "VPCPrivateSubnet1Subnet8BCA10E0"
+     },
+     {
+      "Ref": "VPCPrivateSubnet2SubnetCFCDAA7A"
+     }
+    ]
+   },
+   "UpdatePolicy": {
+    "AutoScalingScheduledAction": {
+     "IgnoreUnmodifiedGroupSizeProperties": true
+    }
+   }
+  },
   "AsgFromMipASG9EFCE2FC": {
    "Type": "AWS::AutoScaling::AutoScalingGroup",
    "Properties": {

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.js.snapshot/cdk.out

@@ -1 +1 @@
-{"version":"21.0.0"}
+{"version":"22.0.0"}

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.js.snapshot/integ.json

@@ -1,5 +1,5 @@
 {
-  "version": "21.0.0",
+  "version": "22.0.0",
   "testCases": {
     "integ.asg-lt": {
       "stacks": [

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.js.snapshot/manifest.json

@@ -1,12 +1,6 @@
 {
-  "version": "21.0.0",
+  "version": "22.0.0",
   "artifacts": {
-    "Tree": {
-      "type": "cdk:tree",
-      "properties": {
-        "file": "tree.json"
-      }
-    },
     "aws-cdk-asg-integ.assets": {
       "type": "cdk:asset-manifest",
       "properties": {
@@ -23,7 +17,7 @@
         "validateOnSynth": false,
         "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-deploy-role-${AWS::AccountId}-${AWS::Region}",
         "cloudFormationExecutionRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-cfn-exec-role-${AWS::AccountId}-${AWS::Region}",
-        "stackTemplateAssetObjectUrl": "s3://cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}/2ca8f144c3e288148d58c9b9e86c9034f6a72b09cecffac3a5d406f8f53d5b18.json",
+        "stackTemplateAssetObjectUrl": "s3://cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}/768b8ff8b1178a04dbfca488da9459f4f402bfad643db0b4791787ef23ec4db5.json",
         "requiresBootstrapStackVersion": 6,
         "bootstrapStackVersionSsmParameter": "/cdk-bootstrap/hnb659fds/version",
         "additionalDependencies": [
@@ -213,6 +207,12 @@
             "data": "AsgFromLTASG089B7C3A"
           }
         ],
+        "/aws-cdk-asg-integ/AsgWithDefaultInstanceWarmup/ASG": [
+          {
+            "type": "aws:cdk:logicalId",
+            "data": "AsgWithDefaultInstanceWarmupASG7A481C66"
+          }
+        ],
         "/aws-cdk-asg-integ/AsgFromMip": [
           {
             "type": "aws:cdk:warning",
@@ -293,6 +293,12 @@
         ]
       },
       "displayName": "aws-cdk-asg-integ"
+    },
+    "Tree": {
+      "type": "cdk:tree",
+      "properties": {
+        "file": "tree.json"
+      }
     }
   }
 }

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.js.snapshot/tree.json

@@ -4,14 +4,6 @@
     "id": "App",
     "path": "",
     "children": {
-      "Tree": {
-        "id": "Tree",
-        "path": "Tree",
-        "constructInfo": {
-          "fqn": "constructs.Construct",
-          "version": "10.1.140"
-        }
-      },
       "aws-cdk-asg-integ": {
         "id": "aws-cdk-asg-integ",
         "path": "aws-cdk-asg-integ",
@@ -856,6 +848,51 @@
               "version": "0.0.0"
             }
           },
+          "AsgWithDefaultInstanceWarmup": {
+            "id": "AsgWithDefaultInstanceWarmup",
+            "path": "aws-cdk-asg-integ/AsgWithDefaultInstanceWarmup",
+            "children": {
+              "ASG": {
+                "id": "ASG",
+                "path": "aws-cdk-asg-integ/AsgWithDefaultInstanceWarmup/ASG",
+                "attributes": {
+                  "aws:cdk:cloudformation:type": "AWS::AutoScaling::AutoScalingGroup",
+                  "aws:cdk:cloudformation:props": {
+                    "maxSize": "1",
+                    "minSize": "1",
+                    "defaultInstanceWarmup": 5,
+                    "launchTemplate": {
+                      "launchTemplateId": {
+                        "Ref": "MainLT4FC09097"
+                      },
+                      "version": {
+                        "Fn::GetAtt": [
+                          "MainLT4FC09097",
+                          "LatestVersionNumber"
+                        ]
+                      }
+                    },
+                    "vpcZoneIdentifier": [
+                      {
+                        "Ref": "VPCPrivateSubnet1Subnet8BCA10E0"
+                      },
+                      {
+                        "Ref": "VPCPrivateSubnet2SubnetCFCDAA7A"
+                      }
+                    ]
+                  }
+                },
+                "constructInfo": {
+                  "fqn": "@aws-cdk/aws-autoscaling.CfnAutoScalingGroup",
+                  "version": "0.0.0"
+                }
+              }
+            },
+            "constructInfo": {
+              "fqn": "@aws-cdk/aws-autoscaling.AutoScalingGroup",
+              "version": "0.0.0"
+            }
+          },
           "AsgFromMip": {
             "id": "AsgFromMip",
             "path": "aws-cdk-asg-integ/AsgFromMip",
@@ -1049,6 +1086,14 @@
                 "id": "InstanceRole",
                 "path": "aws-cdk-asg-integ/AsgWithGp3Blockdevice/InstanceRole",
                 "children": {
+                  "ImportInstanceRole": {
+                    "id": "ImportInstanceRole",
+                    "path": "aws-cdk-asg-integ/AsgWithGp3Blockdevice/InstanceRole/ImportInstanceRole",
+                    "constructInfo": {
+                      "fqn": "@aws-cdk/core.Resource",
+                      "version": "0.0.0"
+                    }
+                  },
                   "Resource": {
                     "id": "Resource",
                     "path": "aws-cdk-asg-integ/AsgWithGp3Blockdevice/InstanceRole/Resource",
@@ -1202,12 +1247,36 @@
               "fqn": "@aws-cdk/core.Resource",
               "version": "0.0.0"
             }
+          },
+          "BootstrapVersion": {
+            "id": "BootstrapVersion",
+            "path": "aws-cdk-asg-integ/BootstrapVersion",
+            "constructInfo": {
+              "fqn": "@aws-cdk/core.CfnParameter",
+              "version": "0.0.0"
+            }
+          },
+          "CheckBootstrapVersion": {
+            "id": "CheckBootstrapVersion",
+            "path": "aws-cdk-asg-integ/CheckBootstrapVersion",
+            "constructInfo": {
+              "fqn": "@aws-cdk/core.CfnRule",
+              "version": "0.0.0"
+            }
           }
         },
         "constructInfo": {
           "fqn": "@aws-cdk/core.Stack",
           "version": "0.0.0"
         }
+      },
+      "Tree": {
+        "id": "Tree",
+        "path": "Tree",
+        "constructInfo": {
+          "fqn": "constructs.Construct",
+          "version": "10.1.168"
+        }
       }
     },
     "constructInfo": {

packages/@aws-cdk/aws-autoscaling/test/integ.asg-lt.ts

@@ -34,6 +34,12 @@ new autoscaling.AutoScalingGroup(stack, 'AsgFromLT', {
   desiredCapacity: 5,
 });
 
+new autoscaling.AutoScalingGroup(stack, 'AsgWithDefaultInstanceWarmup', {
+  vpc,
+  launchTemplate: lt,
+  defaultInstanceWarmup: cdk.Duration.seconds(5),
+});
+
 new autoscaling.AutoScalingGroup(stack, 'AsgFromMip', {
   vpc,
   mixedInstancesPolicy: {