# OnDemandProvisioningSpecificationProperty

The launch specification for On-Demand Instances in the instance fleet, which determines the allocation strategy.

> The instance fleet configuration is available only in Amazon EMR releases 4.8.0 and later, excluding 5.0.x versions. On-Demand Instances allocation strategy is available in Amazon EMR releases 5.12.1 and later.

- Source: Generated code
- Type last changed: v2.162.0 · 10 Oct 2024

## Example

```ts
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import { aws_emr as emr } from 'aws-cdk-lib';
const onDemandProvisioningSpecificationProperty: emr.CfnInstanceFleetConfig.OnDemandProvisioningSpecificationProperty = {
  allocationStrategy: 'allocationStrategy',

  // the properties below are optional
  capacityReservationOptions: {
    capacityReservationPreference: 'capacityReservationPreference',
    capacityReservationResourceGroupArn: 'capacityReservationResourceGroupArn',
    usageStrategy: 'usageStrategy',
  },
};
```

## Properties

- `allocationStrategy`: string (required) — Specifies the strategy to use in launching On-Demand instance fleets.

  Available options are `lowest-price` and `prioritized` . `lowest-price` specifies to launch the instances with the lowest price first, and `prioritized` specifies that Amazon EMR should launch the instances with the highest priority first. The default is `lowest-price` .

- `capacityReservationOptions`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.OnDemandCapacityReservationOptionsProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.OnDemandCapacityReservationOptionsProperty.html) — The launch specification for On-Demand instances in the instance fleet, which determines the allocation strategy.