import type { Construct } from 'constructs';
import type { IPlacementGroupRef, PlacementGroupReference } from './ec2.generated';
import type { IResource } from '../../core';
import { Resource } from '../../core';
/**
 * Determines where your instances are placed on the underlying hardware according to the specified PlacementGroupStrategy
 *
 * @see https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/placement-groups.html
 */
export interface IPlacementGroup extends IResource, IPlacementGroupRef {
    /**
     * The name of this placement group
     *
     * @attribute
     */
    readonly placementGroupName: string;
    /**
     * The number of partitions. Valid only when Strategy is set to PARTITION.
     *
     * @default 0
     */
    readonly partitions?: number;
    /**
     * Places instances on distinct hardware. Spread placement groups are recommended for applications
     * that have a small number of critical instances that should be kept separate from each other.
     * Launching instances in a spread level placement group reduces the risk of simultaneous failures
     * that might occur when instances share the same equipment.
     * Spread level placement groups provide access to distinct hardware,
     * and are therefore suitable for mixing instance types or launching instances over time.
     * If you start or launch an instance in a spread placement group and there is insufficient
     * unique hardware to fulfill the request, the request fails. Amazon EC2 makes more distinct hardware
     * available over time, so you can try your request again later.
     * Placement groups can spread instances across racks or hosts.
     * You can use host level spread placement groups only with AWS Outposts.
     *
     * @default - no spread level
     */
    readonly spreadLevel?: PlacementGroupSpreadLevel;
    /**
     * Which strategy to use when launching instances
     *
     * @default - `PlacementGroupStrategy.PARTITION` if `partitions` is defined, `CLUSTER` otherwise
     */
    readonly strategy?: PlacementGroupStrategy;
}
/**
 * Props for a PlacementGroup
 */
export interface PlacementGroupProps {
    /**
     * the name of this placement group
     *
     * @default - generated by CFN
     *
     * @attribute
     */
    readonly placementGroupName?: string;
    /**
     * The number of partitions. Valid only when Strategy is set to partition.
     *
     * @default 0
     */
    readonly partitions?: number;
    /**
     * Places instances on distinct hardware. Spread placement groups are recommended for applications
     * that have a small number of critical instances that should be kept separate from each other.
     * Launching instances in a spread level placement group reduces the risk of simultaneous failures
     * that might occur when instances share the same equipment.
     * Spread level placement groups provide access to distinct hardware,
     * and are therefore suitable for mixing instance types or launching instances over time.
     * If you start or launch an instance in a spread placement group and there is insufficient
     * unique hardware to fulfill the request, the request fails. Amazon EC2 makes more distinct hardware
     * available over time, so you can try your request again later.
     * Placement groups can spread instances across racks or hosts.
     * You can use host level spread placement groups only with AWS Outposts.
     *
     * @default - no spread level
     */
    readonly spreadLevel?: PlacementGroupSpreadLevel;
    /**
     * Which strategy to use when launching instances
     *
     * @default - `PlacementGroupStrategy.PARTITION` if `partitions` is defined, `CLUSTER` otherwise
     */
    readonly strategy?: PlacementGroupStrategy;
}
/**
 * Determines how this placement group spreads instances
 */
export declare enum PlacementGroupSpreadLevel {
    /**
     * Host spread level placement groups are only available with AWS Outposts.
     * For host spread level placement groups, there are no restrictions for running instances per Outposts.
     *
     * @see https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/placement-groups-outpost.html
     */
    HOST = "host",
    /**
     * Each instance is launched on a separate rack.
     * Each has its own network and power source.
     * A rack spread placement group can span multiple Availability Zones in the same Region.
     * For rack spread level placement groups, you can have a maximum of seven running instances per Availability Zone per group.
     */
    RACK = "rack"
}
/**
 * Which strategy to use when launching instances
 */
export declare enum PlacementGroupStrategy {
    /**
     * Packs instances close together inside an Availability Zone.
     * This strategy enables workloads to achieve the low-latency network
     * performance necessary for tightly-coupled node-to-node communication that
     * is typical of high-performance computing (HPC) applications.
     */
    CLUSTER = "cluster",
    /**
     * Spreads your instances across logical partitions such that groups of instances
     * in one partition do not share the underlying hardware with groups of instances
     * in different partitions.
     *
     * This strategy is typically used by large distributed and replicated workloads,
     * such as Hadoop, Cassandra, and Kafka.
     */
    PARTITION = "partition",
    /**
     * Strictly places a small group of instances across distinct underlying hardware
     * to reduce correlated failures.
     */
    SPREAD = "spread"
}
/**
 * Defines a placement group. Placement groups give you fine-grained control over
 * where your instances are provisioned.
 */
export declare class PlacementGroup extends Resource implements IPlacementGroup {
    /** Uniquely identifies this class. */
    static readonly PROPERTY_INJECTION_ID: string;
    /**
     * Import a PlacementGroup by its arn
     */
    static fromPlacementGroupName(scope: Construct, id: string, placementGroupName: string): IPlacementGroup;
    readonly partitions?: number;
    readonly spreadLevel?: PlacementGroupSpreadLevel;
    readonly strategy?: PlacementGroupStrategy;
    private readonly resource;
    get placementGroupName(): string;
    constructor(scope: Construct, id: string, props?: PlacementGroupProps);
    get placementGroupRef(): PlacementGroupReference;
}