Application Auto Scaling

2017/11/17 - Application Auto Scaling - 2 updated api methods

Changes  This SDK update contains support for Target Tracking scaling for EC2 Spot Fleet. It allows you to scale an EC2 Spot Fleet using a Target Tracking scaling policy.

DescribeScalingPolicies (updated) Link ¶
Changes (response)
{'ScalingPolicies': {'TargetTrackingScalingPolicyConfiguration': {'PredefinedMetricSpecification': {'PredefinedMetricType': {'ALBRequestCountPerTarget',
                                                                                                                             'EC2SpotFleetRequestAverageCPUUtilization',
                                                                                                                             'EC2SpotFleetRequestAverageNetworkIn',
                                                                                                                             'EC2SpotFleetRequestAverageNetworkOut'}}}}}

Describes the scaling policies for the specified service namespace.

You can filter the results using the ResourceId , ScalableDimension , and PolicyNames parameters.

To create a scaling policy or update an existing one, see PutScalingPolicy. If you are no longer using a scaling policy, you can delete it using DeleteScalingPolicy.

See also: AWS API Documentation

Request Syntax

client.describe_scaling_policies(
    PolicyNames=[
        'string',
    ],
    ServiceNamespace='ecs'|'elasticmapreduce'|'ec2'|'appstream'|'dynamodb'|'rds',
    ResourceId='string',
    ScalableDimension='ecs:service:DesiredCount'|'ec2:spot-fleet-request:TargetCapacity'|'elasticmapreduce:instancegroup:InstanceCount'|'appstream:fleet:DesiredCapacity'|'dynamodb:table:ReadCapacityUnits'|'dynamodb:table:WriteCapacityUnits'|'dynamodb:index:ReadCapacityUnits'|'dynamodb:index:WriteCapacityUnits'|'rds:cluster:ReadReplicaCount',
    MaxResults=123,
    NextToken='string'
)
type PolicyNames

list

param PolicyNames

The names of the scaling policies to describe.

  • (string) --

type ServiceNamespace

string

param ServiceNamespace

[REQUIRED]

The namespace of the AWS service. For more information, see AWS Service Namespaces in the Amazon Web Services General Reference .

type ResourceId

string

param ResourceId

The identifier of the resource associated with the scaling policy. This string consists of the resource type and unique identifier. If you specify a scalable dimension, you must also specify a resource ID.

  • ECS service - The resource type is service and the unique identifier is the cluster name and service name. Example: service/default/sample-webapp .

  • Spot fleet request - The resource type is spot-fleet-request and the unique identifier is the Spot fleet request ID. Example: spot-fleet-request/sfr-73fbd2ce-aa30-494c-8788-1cee4EXAMPLE .

  • EMR cluster - The resource type is instancegroup and the unique identifier is the cluster ID and instance group ID. Example: instancegroup/j-2EEZNYKUA1NTV/ig-1791Y4E1L8YI0 .

  • AppStream 2.0 fleet - The resource type is fleet and the unique identifier is the fleet name. Example: fleet/sample-fleet .

  • DynamoDB table - The resource type is table and the unique identifier is the resource ID. Example: table/my-table .

  • DynamoDB global secondary index - The resource type is index and the unique identifier is the resource ID. Example: table/my-table/index/my-table-index .

  • Aurora DB cluster - The resource type is cluster and the unique identifier is the cluster name. Example: cluster:my-db-cluster .

type ScalableDimension

string

param ScalableDimension

The scalable dimension. This string consists of the service namespace, resource type, and scaling property. If you specify a scalable dimension, you must also specify a resource ID.

  • ecs:service:DesiredCount - The desired task count of an ECS service.

  • ec2:spot-fleet-request:TargetCapacity - The target capacity of a Spot fleet request.

  • elasticmapreduce:instancegroup:InstanceCount - The instance count of an EMR Instance Group.

  • appstream:fleet:DesiredCapacity - The desired capacity of an AppStream 2.0 fleet.

  • dynamodb:table:ReadCapacityUnits - The provisioned read capacity for a DynamoDB table.

  • dynamodb:table:WriteCapacityUnits - The provisioned write capacity for a DynamoDB table.

  • dynamodb:index:ReadCapacityUnits - The provisioned read capacity for a DynamoDB global secondary index.

  • dynamodb:index:WriteCapacityUnits - The provisioned write capacity for a DynamoDB global secondary index.

  • rds:cluster:ReadReplicaCount - The count of Aurora Replicas in an Aurora DB cluster. Available for Aurora MySQL-compatible edition.

type MaxResults

integer

param MaxResults

The maximum number of scalable target results. This value can be between 1 and 50. The default value is 50.

If this parameter is used, the operation returns up to MaxResults results at a time, along with a NextToken value. To get the next set of results, include the NextToken value in a subsequent call. If this parameter is not used, the operation returns up to 50 results and a NextToken value, if applicable.

type NextToken

string

param NextToken

The token for the next set of results.

rtype

dict

returns

Response Syntax

{
    'ScalingPolicies': [
        {
            'PolicyARN': 'string',
            'PolicyName': 'string',
            'ServiceNamespace': 'ecs'|'elasticmapreduce'|'ec2'|'appstream'|'dynamodb'|'rds',
            'ResourceId': 'string',
            'ScalableDimension': 'ecs:service:DesiredCount'|'ec2:spot-fleet-request:TargetCapacity'|'elasticmapreduce:instancegroup:InstanceCount'|'appstream:fleet:DesiredCapacity'|'dynamodb:table:ReadCapacityUnits'|'dynamodb:table:WriteCapacityUnits'|'dynamodb:index:ReadCapacityUnits'|'dynamodb:index:WriteCapacityUnits'|'rds:cluster:ReadReplicaCount',
            'PolicyType': 'StepScaling'|'TargetTrackingScaling',
            'StepScalingPolicyConfiguration': {
                'AdjustmentType': 'ChangeInCapacity'|'PercentChangeInCapacity'|'ExactCapacity',
                'StepAdjustments': [
                    {
                        'MetricIntervalLowerBound': 123.0,
                        'MetricIntervalUpperBound': 123.0,
                        'ScalingAdjustment': 123
                    },
                ],
                'MinAdjustmentMagnitude': 123,
                'Cooldown': 123,
                'MetricAggregationType': 'Average'|'Minimum'|'Maximum'
            },
            'TargetTrackingScalingPolicyConfiguration': {
                'TargetValue': 123.0,
                'PredefinedMetricSpecification': {
                    'PredefinedMetricType': 'DynamoDBReadCapacityUtilization'|'DynamoDBWriteCapacityUtilization'|'ALBRequestCountPerTarget'|'RDSReaderAverageCPUUtilization'|'RDSReaderAverageDatabaseConnections'|'EC2SpotFleetRequestAverageCPUUtilization'|'EC2SpotFleetRequestAverageNetworkIn'|'EC2SpotFleetRequestAverageNetworkOut',
                    'ResourceLabel': 'string'
                },
                'CustomizedMetricSpecification': {
                    'MetricName': 'string',
                    'Namespace': 'string',
                    'Dimensions': [
                        {
                            'Name': 'string',
                            'Value': 'string'
                        },
                    ],
                    'Statistic': 'Average'|'Minimum'|'Maximum'|'SampleCount'|'Sum',
                    'Unit': 'string'
                },
                'ScaleOutCooldown': 123,
                'ScaleInCooldown': 123,
                'DisableScaleIn': True|False
            },
            'Alarms': [
                {
                    'AlarmName': 'string',
                    'AlarmARN': 'string'
                },
            ],
            'CreationTime': datetime(2015, 1, 1)
        },
    ],
    'NextToken': 'string'
}

Response Structure

  • (dict) --

    • ScalingPolicies (list) --

      Information about the scaling policies.

      • (dict) --

        Represents a scaling policy.

        • PolicyARN (string) --

          The Amazon Resource Name (ARN) of the scaling policy.

        • PolicyName (string) --

          The name of the scaling policy.

        • ServiceNamespace (string) --

          The namespace of the AWS service. For more information, see AWS Service Namespaces in the Amazon Web Services General Reference .

        • ResourceId (string) --

          The identifier of the resource associated with the scaling policy. This string consists of the resource type and unique identifier.

          • ECS service - The resource type is service and the unique identifier is the cluster name and service name. Example: service/default/sample-webapp .

          • Spot fleet request - The resource type is spot-fleet-request and the unique identifier is the Spot fleet request ID. Example: spot-fleet-request/sfr-73fbd2ce-aa30-494c-8788-1cee4EXAMPLE .

          • EMR cluster - The resource type is instancegroup and the unique identifier is the cluster ID and instance group ID. Example: instancegroup/j-2EEZNYKUA1NTV/ig-1791Y4E1L8YI0 .

          • AppStream 2.0 fleet - The resource type is fleet and the unique identifier is the fleet name. Example: fleet/sample-fleet .

          • DynamoDB table - The resource type is table and the unique identifier is the resource ID. Example: table/my-table .

          • DynamoDB global secondary index - The resource type is index and the unique identifier is the resource ID. Example: table/my-table/index/my-table-index .

          • Aurora DB cluster - The resource type is cluster and the unique identifier is the cluster name. Example: cluster:my-db-cluster .

        • ScalableDimension (string) --

          The scalable dimension. This string consists of the service namespace, resource type, and scaling property.

          • ecs:service:DesiredCount - The desired task count of an ECS service.

          • ec2:spot-fleet-request:TargetCapacity - The target capacity of a Spot fleet request.

          • elasticmapreduce:instancegroup:InstanceCount - The instance count of an EMR Instance Group.

          • appstream:fleet:DesiredCapacity - The desired capacity of an AppStream 2.0 fleet.

          • dynamodb:table:ReadCapacityUnits - The provisioned read capacity for a DynamoDB table.

          • dynamodb:table:WriteCapacityUnits - The provisioned write capacity for a DynamoDB table.

          • dynamodb:index:ReadCapacityUnits - The provisioned read capacity for a DynamoDB global secondary index.

          • dynamodb:index:WriteCapacityUnits - The provisioned write capacity for a DynamoDB global secondary index.

          • rds:cluster:ReadReplicaCount - The count of Aurora Replicas in an Aurora DB cluster. Available for Aurora MySQL-compatible edition.

        • PolicyType (string) --

          The scaling policy type.

        • StepScalingPolicyConfiguration (dict) --

          A step scaling policy.

          • AdjustmentType (string) --

            The adjustment type, which specifies how the ScalingAdjustment parameter in a StepAdjustment is interpreted.

          • StepAdjustments (list) --

            A set of adjustments that enable you to scale based on the size of the alarm breach.

            • (dict) --

              Represents a step adjustment for a StepScalingPolicyConfiguration. Describes an adjustment based on the difference between the value of the aggregated CloudWatch metric and the breach threshold that you've defined for the alarm.

              For the following examples, suppose that you have an alarm with a breach threshold of 50:

              • To trigger the adjustment when the metric is greater than or equal to 50 and less than 60, specify a lower bound of 0 and an upper bound of 10.

              • To trigger the adjustment when the metric is greater than 40 and less than or equal to 50, specify a lower bound of -10 and an upper bound of 0.

              There are a few rules for the step adjustments for your step policy:

              • The ranges of your step adjustments can't overlap or have a gap.

              • At most one step adjustment can have a null lower bound. If one step adjustment has a negative lower bound, then there must be a step adjustment with a null lower bound.

              • At most one step adjustment can have a null upper bound. If one step adjustment has a positive upper bound, then there must be a step adjustment with a null upper bound.

              • The upper and lower bound can't be null in the same step adjustment.

              • MetricIntervalLowerBound (float) --

                The lower bound for the difference between the alarm threshold and the CloudWatch metric. If the metric value is above the breach threshold, the lower bound is inclusive (the metric must be greater than or equal to the threshold plus the lower bound). Otherwise, it is exclusive (the metric must be greater than the threshold plus the lower bound). A null value indicates negative infinity.

              • MetricIntervalUpperBound (float) --

                The upper bound for the difference between the alarm threshold and the CloudWatch metric. If the metric value is above the breach threshold, the upper bound is exclusive (the metric must be less than the threshold plus the upper bound). Otherwise, it is inclusive (the metric must be less than or equal to the threshold plus the upper bound). A null value indicates positive infinity.

                The upper bound must be greater than the lower bound.

              • ScalingAdjustment (integer) --

                The amount by which to scale, based on the specified adjustment type. A positive value adds to the current scalable dimension while a negative number removes from the current scalable dimension.

          • MinAdjustmentMagnitude (integer) --

            The minimum number to adjust your scalable dimension as a result of a scaling activity. If the adjustment type is PercentChangeInCapacity , the scaling policy changes the scalable dimension of the scalable target by this amount.

          • Cooldown (integer) --

            The amount of time, in seconds, after a scaling activity completes where previous trigger-related scaling activities can influence future scaling events.

            For scale out policies, while the cooldown period is in effect, the capacity that has been added by the previous scale out event that initiated the cooldown is calculated as part of the desired capacity for the next scale out. The intention is to continuously (but not excessively) scale out. For example, an alarm triggers a step scaling policy to scale out an Amazon ECS service by 2 tasks, the scaling activity completes successfully, and a cooldown period of 5 minutes starts. During the Cooldown period, if the alarm triggers the same policy again but at a more aggressive step adjustment to scale out the service by 3 tasks, the 2 tasks that were added in the previous scale out event are considered part of that capacity and only 1 additional task is added to the desired count.

            For scale in policies, the cooldown period is used to block subsequent scale in requests until it has expired. The intention is to scale in conservatively to protect your application's availability. However, if another alarm triggers a scale out policy during the cooldown period after a scale-in, Application Auto Scaling scales out your scalable target immediately.

          • MetricAggregationType (string) --

            The aggregation type for the CloudWatch metrics. Valid values are Minimum , Maximum , and Average .

        • TargetTrackingScalingPolicyConfiguration (dict) --

          A target tracking policy.

          • TargetValue (float) --

            The target value for the metric. The range is 8.515920e-109 to 1.174271e+108 (Base 10) or 2e-360 to 2e360 (Base 2).

          • PredefinedMetricSpecification (dict) --

            A predefined metric.

            • PredefinedMetricType (string) --

              The metric type. The ALBRequestCountPerTarget metric type applies only to Spot fleet requests.

            • ResourceLabel (string) --

              Identifies the resource associated with the metric type. You can't specify a resource label unless the metric type is ALBRequestCountPerTarget and there is a target group attached to the Spot fleet request.

              The format is app/<load-balancer-name>/<load-balancer-id>/targetgroup/<target-group-name>/<target-group-id>, where:

              • app/<load-balancer-name>/<load-balancer-id> is the final portion of the load balancer ARN

              • targetgroup/<target-group-name>/<target-group-id> is the final portion of the target group ARN.

          • CustomizedMetricSpecification (dict) --

            Reserved for future use.

            • MetricName (string) --

              The name of the metric.

            • Namespace (string) --

              The namespace of the metric.

            • Dimensions (list) --

              The dimensions of the metric.

              • (dict) --

                Describes the dimension of a metric.

                • Name (string) --

                  The name of the dimension.

                • Value (string) --

                  The value of the dimension.

            • Statistic (string) --

              The statistic of the metric.

            • Unit (string) --

              The unit of the metric.

          • ScaleOutCooldown (integer) --

            The amount of time, in seconds, after a scale out activity completes before another scale out activity can start.

            While the cooldown period is in effect, the capacity that has been added by the previous scale out event that initiated the cooldown is calculated as part of the desired capacity for the next scale out. The intention is to continuously (but not excessively) scale out.

          • ScaleInCooldown (integer) --

            The amount of time, in seconds, after a scale in activity completes before another scale in activity can start.

            The cooldown period is used to block subsequent scale in requests until it has expired. The intention is to scale in conservatively to protect your application's availability. However, if another alarm triggers a scale out policy during the cooldown period after a scale-in, Application Auto Scaling scales out your scalable target immediately.

          • DisableScaleIn (boolean) --

            Indicates whether scale in by the target tracking policy is disabled. If the value is true , scale in is disabled and the target tracking policy won't remove capacity from the scalable resource. Otherwise, scale in is enabled and the target tracking policy can remove capacity from the scalable resource. The default value is false .

        • Alarms (list) --

          The CloudWatch alarms associated with the scaling policy.

          • (dict) --

            Represents a CloudWatch alarm associated with a scaling policy.

            • AlarmName (string) --

              The name of the alarm.

            • AlarmARN (string) --

              The Amazon Resource Name (ARN) of the alarm.

        • CreationTime (datetime) --

          The Unix timestamp for when the scaling policy was created.

    • NextToken (string) --

      The token required to get the next set of results. This value is null if there are no more results to return.

PutScalingPolicy (updated) Link ¶
Changes (request)
{'TargetTrackingScalingPolicyConfiguration': {'PredefinedMetricSpecification': {'PredefinedMetricType': {'ALBRequestCountPerTarget',
                                                                                                         'EC2SpotFleetRequestAverageCPUUtilization',
                                                                                                         'EC2SpotFleetRequestAverageNetworkIn',
                                                                                                         'EC2SpotFleetRequestAverageNetworkOut'}}}}

Creates or updates a policy for an Application Auto Scaling scalable target.

Each scalable target is identified by a service namespace, resource ID, and scalable dimension. A scaling policy applies to the scalable target identified by those three attributes. You cannot create a scaling policy without first registering a scalable target using RegisterScalableTarget.

To update a policy, specify its policy name and the parameters that you want to change. Any parameters that you don't specify are not changed by this update request.

You can view the scaling policies for a service namespace using DescribeScalingPolicies. If you are no longer using a scaling policy, you can delete it using DeleteScalingPolicy.

See also: AWS API Documentation

Request Syntax

client.put_scaling_policy(
    PolicyName='string',
    ServiceNamespace='ecs'|'elasticmapreduce'|'ec2'|'appstream'|'dynamodb'|'rds',
    ResourceId='string',
    ScalableDimension='ecs:service:DesiredCount'|'ec2:spot-fleet-request:TargetCapacity'|'elasticmapreduce:instancegroup:InstanceCount'|'appstream:fleet:DesiredCapacity'|'dynamodb:table:ReadCapacityUnits'|'dynamodb:table:WriteCapacityUnits'|'dynamodb:index:ReadCapacityUnits'|'dynamodb:index:WriteCapacityUnits'|'rds:cluster:ReadReplicaCount',
    PolicyType='StepScaling'|'TargetTrackingScaling',
    StepScalingPolicyConfiguration={
        'AdjustmentType': 'ChangeInCapacity'|'PercentChangeInCapacity'|'ExactCapacity',
        'StepAdjustments': [
            {
                'MetricIntervalLowerBound': 123.0,
                'MetricIntervalUpperBound': 123.0,
                'ScalingAdjustment': 123
            },
        ],
        'MinAdjustmentMagnitude': 123,
        'Cooldown': 123,
        'MetricAggregationType': 'Average'|'Minimum'|'Maximum'
    },
    TargetTrackingScalingPolicyConfiguration={
        'TargetValue': 123.0,
        'PredefinedMetricSpecification': {
            'PredefinedMetricType': 'DynamoDBReadCapacityUtilization'|'DynamoDBWriteCapacityUtilization'|'ALBRequestCountPerTarget'|'RDSReaderAverageCPUUtilization'|'RDSReaderAverageDatabaseConnections'|'EC2SpotFleetRequestAverageCPUUtilization'|'EC2SpotFleetRequestAverageNetworkIn'|'EC2SpotFleetRequestAverageNetworkOut',
            'ResourceLabel': 'string'
        },
        'CustomizedMetricSpecification': {
            'MetricName': 'string',
            'Namespace': 'string',
            'Dimensions': [
                {
                    'Name': 'string',
                    'Value': 'string'
                },
            ],
            'Statistic': 'Average'|'Minimum'|'Maximum'|'SampleCount'|'Sum',
            'Unit': 'string'
        },
        'ScaleOutCooldown': 123,
        'ScaleInCooldown': 123,
        'DisableScaleIn': True|False
    }
)
type PolicyName

string

param PolicyName

[REQUIRED]

The name of the scaling policy.

type ServiceNamespace

string

param ServiceNamespace

[REQUIRED]

The namespace of the AWS service. For more information, see AWS Service Namespaces in the Amazon Web Services General Reference .

type ResourceId

string

param ResourceId

[REQUIRED]

The identifier of the resource associated with the scaling policy. This string consists of the resource type and unique identifier.

  • ECS service - The resource type is service and the unique identifier is the cluster name and service name. Example: service/default/sample-webapp .

  • Spot fleet request - The resource type is spot-fleet-request and the unique identifier is the Spot fleet request ID. Example: spot-fleet-request/sfr-73fbd2ce-aa30-494c-8788-1cee4EXAMPLE .

  • EMR cluster - The resource type is instancegroup and the unique identifier is the cluster ID and instance group ID. Example: instancegroup/j-2EEZNYKUA1NTV/ig-1791Y4E1L8YI0 .

  • AppStream 2.0 fleet - The resource type is fleet and the unique identifier is the fleet name. Example: fleet/sample-fleet .

  • DynamoDB table - The resource type is table and the unique identifier is the resource ID. Example: table/my-table .

  • DynamoDB global secondary index - The resource type is index and the unique identifier is the resource ID. Example: table/my-table/index/my-table-index .

  • Aurora DB cluster - The resource type is cluster and the unique identifier is the cluster name. Example: cluster:my-db-cluster .

type ScalableDimension

string

param ScalableDimension

[REQUIRED]

The scalable dimension. This string consists of the service namespace, resource type, and scaling property.

  • ecs:service:DesiredCount - The desired task count of an ECS service.

  • ec2:spot-fleet-request:TargetCapacity - The target capacity of a Spot fleet request.

  • elasticmapreduce:instancegroup:InstanceCount - The instance count of an EMR Instance Group.

  • appstream:fleet:DesiredCapacity - The desired capacity of an AppStream 2.0 fleet.

  • dynamodb:table:ReadCapacityUnits - The provisioned read capacity for a DynamoDB table.

  • dynamodb:table:WriteCapacityUnits - The provisioned write capacity for a DynamoDB table.

  • dynamodb:index:ReadCapacityUnits - The provisioned read capacity for a DynamoDB global secondary index.

  • dynamodb:index:WriteCapacityUnits - The provisioned write capacity for a DynamoDB global secondary index.

  • rds:cluster:ReadReplicaCount - The count of Aurora Replicas in an Aurora DB cluster. Available for Aurora MySQL-compatible edition.

type PolicyType

string

param PolicyType

The policy type. If you are creating a new policy, this parameter is required. If you are updating a policy, this parameter is not required.

For DynamoDB, only TargetTrackingScaling is supported. For any other service, only StepScaling is supported.

type StepScalingPolicyConfiguration

dict

param StepScalingPolicyConfiguration

A step scaling policy.

This parameter is required if you are creating a policy and the policy type is StepScaling .

  • AdjustmentType (string) --

    The adjustment type, which specifies how the ScalingAdjustment parameter in a StepAdjustment is interpreted.

  • StepAdjustments (list) --

    A set of adjustments that enable you to scale based on the size of the alarm breach.

    • (dict) --

      Represents a step adjustment for a StepScalingPolicyConfiguration. Describes an adjustment based on the difference between the value of the aggregated CloudWatch metric and the breach threshold that you've defined for the alarm.

      For the following examples, suppose that you have an alarm with a breach threshold of 50:

      • To trigger the adjustment when the metric is greater than or equal to 50 and less than 60, specify a lower bound of 0 and an upper bound of 10.

      • To trigger the adjustment when the metric is greater than 40 and less than or equal to 50, specify a lower bound of -10 and an upper bound of 0.

      There are a few rules for the step adjustments for your step policy:

      • The ranges of your step adjustments can't overlap or have a gap.

      • At most one step adjustment can have a null lower bound. If one step adjustment has a negative lower bound, then there must be a step adjustment with a null lower bound.

      • At most one step adjustment can have a null upper bound. If one step adjustment has a positive upper bound, then there must be a step adjustment with a null upper bound.

      • The upper and lower bound can't be null in the same step adjustment.

      • MetricIntervalLowerBound (float) --

        The lower bound for the difference between the alarm threshold and the CloudWatch metric. If the metric value is above the breach threshold, the lower bound is inclusive (the metric must be greater than or equal to the threshold plus the lower bound). Otherwise, it is exclusive (the metric must be greater than the threshold plus the lower bound). A null value indicates negative infinity.

      • MetricIntervalUpperBound (float) --

        The upper bound for the difference between the alarm threshold and the CloudWatch metric. If the metric value is above the breach threshold, the upper bound is exclusive (the metric must be less than the threshold plus the upper bound). Otherwise, it is inclusive (the metric must be less than or equal to the threshold plus the upper bound). A null value indicates positive infinity.

        The upper bound must be greater than the lower bound.

      • ScalingAdjustment (integer) -- [REQUIRED]

        The amount by which to scale, based on the specified adjustment type. A positive value adds to the current scalable dimension while a negative number removes from the current scalable dimension.

  • MinAdjustmentMagnitude (integer) --

    The minimum number to adjust your scalable dimension as a result of a scaling activity. If the adjustment type is PercentChangeInCapacity , the scaling policy changes the scalable dimension of the scalable target by this amount.

  • Cooldown (integer) --

    The amount of time, in seconds, after a scaling activity completes where previous trigger-related scaling activities can influence future scaling events.

    For scale out policies, while the cooldown period is in effect, the capacity that has been added by the previous scale out event that initiated the cooldown is calculated as part of the desired capacity for the next scale out. The intention is to continuously (but not excessively) scale out. For example, an alarm triggers a step scaling policy to scale out an Amazon ECS service by 2 tasks, the scaling activity completes successfully, and a cooldown period of 5 minutes starts. During the Cooldown period, if the alarm triggers the same policy again but at a more aggressive step adjustment to scale out the service by 3 tasks, the 2 tasks that were added in the previous scale out event are considered part of that capacity and only 1 additional task is added to the desired count.

    For scale in policies, the cooldown period is used to block subsequent scale in requests until it has expired. The intention is to scale in conservatively to protect your application's availability. However, if another alarm triggers a scale out policy during the cooldown period after a scale-in, Application Auto Scaling scales out your scalable target immediately.

  • MetricAggregationType (string) --

    The aggregation type for the CloudWatch metrics. Valid values are Minimum , Maximum , and Average .

type TargetTrackingScalingPolicyConfiguration

dict

param TargetTrackingScalingPolicyConfiguration

A target tracking policy.

This parameter is required if you are creating a new policy and the policy type is TargetTrackingScaling .

  • TargetValue (float) -- [REQUIRED]

    The target value for the metric. The range is 8.515920e-109 to 1.174271e+108 (Base 10) or 2e-360 to 2e360 (Base 2).

  • PredefinedMetricSpecification (dict) --

    A predefined metric.

    • PredefinedMetricType (string) -- [REQUIRED]

      The metric type. The ALBRequestCountPerTarget metric type applies only to Spot fleet requests.

    • ResourceLabel (string) --

      Identifies the resource associated with the metric type. You can't specify a resource label unless the metric type is ALBRequestCountPerTarget and there is a target group attached to the Spot fleet request.

      The format is app/<load-balancer-name>/<load-balancer-id>/targetgroup/<target-group-name>/<target-group-id>, where:

      • app/<load-balancer-name>/<load-balancer-id> is the final portion of the load balancer ARN

      • targetgroup/<target-group-name>/<target-group-id> is the final portion of the target group ARN.

  • CustomizedMetricSpecification (dict) --

    Reserved for future use.

    • MetricName (string) -- [REQUIRED]

      The name of the metric.

    • Namespace (string) -- [REQUIRED]

      The namespace of the metric.

    • Dimensions (list) --

      The dimensions of the metric.

      • (dict) --

        Describes the dimension of a metric.

        • Name (string) -- [REQUIRED]

          The name of the dimension.

        • Value (string) -- [REQUIRED]

          The value of the dimension.

    • Statistic (string) -- [REQUIRED]

      The statistic of the metric.

    • Unit (string) --

      The unit of the metric.

  • ScaleOutCooldown (integer) --

    The amount of time, in seconds, after a scale out activity completes before another scale out activity can start.

    While the cooldown period is in effect, the capacity that has been added by the previous scale out event that initiated the cooldown is calculated as part of the desired capacity for the next scale out. The intention is to continuously (but not excessively) scale out.

  • ScaleInCooldown (integer) --

    The amount of time, in seconds, after a scale in activity completes before another scale in activity can start.

    The cooldown period is used to block subsequent scale in requests until it has expired. The intention is to scale in conservatively to protect your application's availability. However, if another alarm triggers a scale out policy during the cooldown period after a scale-in, Application Auto Scaling scales out your scalable target immediately.

  • DisableScaleIn (boolean) --

    Indicates whether scale in by the target tracking policy is disabled. If the value is true , scale in is disabled and the target tracking policy won't remove capacity from the scalable resource. Otherwise, scale in is enabled and the target tracking policy can remove capacity from the scalable resource. The default value is false .

rtype

dict

returns

Response Syntax

{
    'PolicyARN': 'string',
    'Alarms': [
        {
            'AlarmName': 'string',
            'AlarmARN': 'string'
        },
    ]
}

Response Structure

  • (dict) --

    • PolicyARN (string) --

      The Amazon Resource Name (ARN) of the resulting scaling policy.

    • Alarms (list) --

      The CloudWatch alarms created for the target tracking policy.

      • (dict) --

        Represents a CloudWatch alarm associated with a scaling policy.

        • AlarmName (string) --

          The name of the alarm.

        • AlarmARN (string) --

          The Amazon Resource Name (ARN) of the alarm.