# WarmUpConfigurationProperty

The configuration settings that define the warm-up behavior for an alarm.

Use these settings to delay alarm evaluation after you create or update the alarm, which reduces alarm noise while a new resource or service starts publishing data.
 During the warm-up period, the alarm stays in ``INSUFFICIENT_DATA`` and does not perform alarm actions.

- Source: Generated code
- Type last changed: v2.268.0 · 2 Sep 2026

## Example

```ts
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import { aws_cloudwatch as cloudwatch } from 'aws-cdk-lib';
const warmUpConfigurationProperty: cloudwatch.CfnAlarm.WarmUpConfigurationProperty = {
  onlyStartEvaluatingAfterWarmUpPeriodEnds: false,
  warmUpPeriodDurationInMinutes: 123,
};
```

## Properties

- `onlyStartEvaluatingAfterWarmUpPeriodEnds`: boolean | [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) — Specifies whether the alarm waits for the full warm-up period before it starts to evaluate.

  The default is ``false``. If ``true``, the alarm waits the entire ``WarmUpPeriodDurationInMinutes`` before it starts to evaluate, even if metric data arrives earlier. If ``false``, the alarm ends the warm-up period early. Evaluation begins as soon as the alarm has enough metric data to fill its evaluation window.

- `warmUpPeriodDurationInMinutes`: number — The length of the warm-up period, in minutes.

  After you create or update the alarm, the alarm stays in ``INSUFFICIENT_DATA`` for this duration. During this time, the alarm does not perform alarm actions.
   You can change this value at any time, including after the warm-up period ends. If you change it after the warm-up period ends, the new value does not restart the warm-up period.