class StepScalingPolicy (construct)
Language | Type name |
---|---|
.NET | Amazon.CDK.AWS.ApplicationAutoScaling.StepScalingPolicy |
Java | software.amazon.awscdk.services.applicationautoscaling.StepScalingPolicy |
Python | aws_cdk.aws_applicationautoscaling.StepScalingPolicy |
TypeScript (source) | @aws-cdk/aws-applicationautoscaling » StepScalingPolicy |
Implements
IConstruct
, IConstruct
, IDependable
Define a scaling strategy which scales depending on absolute values of some metric.
You can specify the scaling behavior for various values of the metric.
Implemented using one or more CloudWatch alarms and Step Scaling Policies.
Example
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import * as appscaling from '@aws-cdk/aws-applicationautoscaling';
import * as cloudwatch from '@aws-cdk/aws-cloudwatch';
import * as cdk from '@aws-cdk/core';
declare const metric: cloudwatch.Metric;
declare const scalableTarget: appscaling.ScalableTarget;
const stepScalingPolicy = new appscaling.StepScalingPolicy(this, 'MyStepScalingPolicy', {
metric: metric,
scalingSteps: [{
change: 123,
// the properties below are optional
lower: 123,
upper: 123,
}],
scalingTarget: scalableTarget,
// the properties below are optional
adjustmentType: appscaling.AdjustmentType.CHANGE_IN_CAPACITY,
cooldown: cdk.Duration.minutes(30),
datapointsToAlarm: 123,
evaluationPeriods: 123,
metricAggregationType: appscaling.MetricAggregationType.AVERAGE,
minAdjustmentMagnitude: 123,
});
Initializer
new StepScalingPolicy(scope: Construct, id: string, props: StepScalingPolicyProps)
Parameters
- scope
Construct
- id
string
- props
Step
Scaling Policy Props
Construct Props
Name | Type | Description |
---|---|---|
metric | IMetric | Metric to scale on. |
scaling | Scaling [] | The intervals for scaling. |
scaling | IScalable | The scaling target. |
adjustment | Adjustment | How the adjustment numbers inside 'intervals' are interpreted. |
cooldown? | Duration | Grace period after scaling activity. |
datapoints | number | The number of data points out of the evaluation periods that must be breaching to trigger a scaling action. |
evaluation | number | How many evaluation periods of the metric to wait before triggering a scaling action. |
metric | Metric | Aggregation to apply to all data points over the evaluation periods. |
min | number | Minimum absolute number to adjust capacity with as result of percentage scaling. |
metric
Type:
IMetric
Metric to scale on.
scalingSteps
Type:
Scaling
[]
The intervals for scaling.
Maps a range of metric values to a particular scaling behavior.
scalingTarget
Type:
IScalable
The scaling target.
adjustmentType?
Type:
Adjustment
(optional, default: ChangeInCapacity)
How the adjustment numbers inside 'intervals' are interpreted.
cooldown?
Type:
Duration
(optional, default: No cooldown period)
Grace period after scaling activity.
Subsequent scale outs during the cooldown period are squashed so that only the biggest scale out happens.
Subsequent scale ins during the cooldown period are ignored.
datapointsToAlarm?
Type:
number
(optional, default: evaluationPeriods
)
The number of data points out of the evaluation periods that must be breaching to trigger a scaling action.
Creates an "M out of N" alarm, where this property is the M and the value set for
evaluationPeriods
is the N value.
Only has meaning if evaluationPeriods != 1
.
evaluationPeriods?
Type:
number
(optional, default: 1)
How many evaluation periods of the metric to wait before triggering a scaling action.
Raising this value can be used to smooth out the metric, at the expense of slower response times.
If datapointsToAlarm
is not set, then all data points in the evaluation period
must meet the criteria to trigger a scaling action.
metricAggregationType?
Type:
Metric
(optional, default: The statistic from the metric if applicable (MIN, MAX, AVERAGE), otherwise AVERAGE.)
Aggregation to apply to all data points over the evaluation periods.
Only has meaning if evaluationPeriods != 1
.
minAdjustmentMagnitude?
Type:
number
(optional, default: No minimum scaling effect)
Minimum absolute number to adjust capacity with as result of percentage scaling.
Only when using AdjustmentType = PercentChangeInCapacity, this number controls the minimum absolute effect size.
Properties
Name | Type | Description |
---|---|---|
node | Construct | The construct tree node associated with this construct. |
lower | Step | |
lower | Alarm | |
upper | Step | |
upper | Alarm |
node
Type:
Construct
The construct tree node associated with this construct.
lowerAction?
Type:
Step
(optional)
lowerAlarm?
Type:
Alarm
(optional)
upperAction?
Type:
Step
(optional)
upperAlarm?
Type:
Alarm
(optional)
Methods
Name | Description |
---|---|
to | Returns a string representation of this construct. |
String()
topublic toString(): string
Returns
string
Returns a string representation of this construct.