feat(ecs): add support for elastic inference accelerators in ECS task…

… defintions (#13950)

This PR would enable users to attach inference accelerators to their ECS tasks (currently not supported by Fargate). It adds an optional `inferenceAccelerators` property to the EC2 Task Definition. It also adds `resourceRequirement` property to the Container definition to enable containers to refer to the inference accelerators provided in the task definition.  

Closes #12460 

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-ecs/README.md

@@ -788,3 +788,39 @@ new ecs.FargateService(stack, 'FargateService', {
 
 app.synth();
 ```
+
+## Elastic Inference Accelerators
+
+Currently, this feature is only supported for services with EC2 launch types.
+
+To add elastic inference accelerators to your EC2 instance, first add
+`inferenceAccelerator` field to the EC2TaskDefinition and set the `deviceName`
+and `deviceType` properties.
+
+```ts
+const inferenceAccelerators = [{
+  deviceName: 'device1',
+  deviceType: 'eia2.medium',
+}];
+
+const taskDefinition = new ecs.Ec2TaskDefinition(stack, 'Ec2TaskDef', {
+  inferenceAccelerators,
+});
+```
+
+To enable using the inference accelerator in the containers, set the
+`type` and `value` properties accordingly. The `value` should match the
+`DeviceName` for an `InferenceAccelerator` specified in a task definition. 
+
+```ts
+const resourceRequirements = [{
+  type: ecs.ResourceRequirementType.INFERENCEACCELERATOR,
+  value: 'device1',
+}];
+
+taskDefinition.addContainer('cont', {
+  image: ecs.ContainerImage.fromRegistry('test'),
+  memoryLimitMiB: 1024,
+  resourceRequirements,
+});
+```

packages/@aws-cdk/aws-ecs/lib/base/task-definition.ts

@@ -184,6 +184,15 @@ export interface TaskDefinitionProps extends CommonTaskDefinitionProps {
    * @default - PidMode used by the task is not specified
    */
   readonly pidMode?: PidMode;
+
+  /**
+   * The inference accelerators to use for the containers in the task.
+   *
+   * Not supported in Fargate.
+   *
+   * @default - No inference accelerators.
+   */
+  readonly inferenceAccelerators?: InferenceAccelerator[];
 }
 
 /**
@@ -322,6 +331,11 @@ export class TaskDefinition extends TaskDefinitionBase {
    */
   private readonly placementConstraints = new Array<CfnTaskDefinition.TaskDefinitionPlacementConstraintProperty>();
 
+  /**
+   * Inference accelerators for task instances
+   */
+  private readonly _inferenceAccelerators: InferenceAccelerator[] = [];
+
   private _executionRole?: iam.IRole;
 
   private _referencesSecretJsonField?: boolean;
@@ -354,12 +368,20 @@ export class TaskDefinition extends TaskDefinitionBase {
       throw new Error(`Fargate-compatible tasks require both CPU (${props.cpu}) and memory (${props.memoryMiB}) specifications`);
     }
 
+    if (props.inferenceAccelerators && props.inferenceAccelerators.length > 0 && this.isFargateCompatible) {
+      throw new Error('Cannot use inference accelerators on tasks that run on Fargate');
+    }
+
     this._executionRole = props.executionRole;
 
     this.taskRole = props.taskRole || new iam.Role(this, 'TaskRole', {
       assumedBy: new iam.ServicePrincipal('ecs-tasks.amazonaws.com'),
     });
 
+    if (props.inferenceAccelerators) {
+      props.inferenceAccelerators.forEach(ia => this.addInferenceAccelerator(ia));
+    }
+
     const taskDef = new CfnTaskDefinition(this, 'Resource', {
       containerDefinitions: Lazy.any({ produce: () => this.renderContainers() }, { omitEmptyArray: true }),
       volumes: Lazy.any({ produce: () => this.renderVolumes() }, { omitEmptyArray: true }),
@@ -380,6 +402,10 @@ export class TaskDefinition extends TaskDefinitionBase {
       memory: props.memoryMiB,
       ipcMode: props.ipcMode,
       pidMode: props.pidMode,
+      inferenceAccelerators: Lazy.any({
+        produce: () =>
+          !isFargateCompatible(this.compatibility) ? this.renderInferenceAccelerators() : undefined,
+      }, { omitEmptyArray: true }),
     });
 
     if (props.placementConstraints) {
@@ -393,6 +419,13 @@ export class TaskDefinition extends TaskDefinitionBase {
     return this._executionRole;
   }
 
+  /**
+   * Public getter method to access list of inference accelerators attached to the instance.
+   */
+  public get inferenceAccelerators(): InferenceAccelerator[] {
+    return this._inferenceAccelerators;
+  }
+
   private renderVolumes(): CfnTaskDefinition.VolumeProperty[] {
     return this.volumes.map(renderVolume);
 
@@ -419,6 +452,17 @@ export class TaskDefinition extends TaskDefinitionBase {
     }
   }
 
+  private renderInferenceAccelerators(): CfnTaskDefinition.InferenceAcceleratorProperty[] {
+    return this._inferenceAccelerators.map(renderInferenceAccelerator);
+
+    function renderInferenceAccelerator(inferenceAccelerator: InferenceAccelerator) : CfnTaskDefinition.InferenceAcceleratorProperty {
+      return {
+        deviceName: inferenceAccelerator.deviceName,
+        deviceType: inferenceAccelerator.deviceType,
+      };
+    }
+  }
+
   /**
    * Validate the existence of the input target and set default values.
    *
@@ -531,6 +575,16 @@ export class TaskDefinition extends TaskDefinitionBase {
     extension.extend(this);
   }
 
+  /**
+   * Adds an inference accelerator to the task definition.
+   */
+  public addInferenceAccelerator(inferenceAccelerator: InferenceAccelerator) {
+    if (isFargateCompatible(this.compatibility)) {
+      throw new Error('Cannot use inference accelerators on tasks that run on Fargate');
+    }
+    this._inferenceAccelerators.push(inferenceAccelerator);
+  }
+
   /**
    * Creates the task execution IAM role if it doesn't already exist.
    */
@@ -683,6 +737,24 @@ export enum PidMode {
   TASK = 'task',
 }
 
+/**
+ * Elastic Inference Accelerator.
+ * For more information, see [Elastic Inference Basics](https://docs.aws.amazon.com/elastic-inference/latest/developerguide/basics.html)
+ */
+export interface InferenceAccelerator {
+  /**
+   * The Elastic Inference accelerator device name.
+   * @default - empty
+   */
+  readonly deviceName?: string;
+
+  /**
+   * The Elastic Inference accelerator type to use. The allowed values are: eia2.medium, eia2.large and eia2.xlarge.
+   * @default - empty
+   */
+  readonly deviceType?: string;
+}
+
 /**
  * A data volume used in a task definition.
  *

packages/@aws-cdk/aws-ecs/lib/container-definition.ts

@@ -294,6 +294,12 @@ export interface ContainerDefinitionOptions {
    * @default - No ports are mapped.
    */
   readonly portMappings?: PortMapping[];
+
+  /**
+   * The inference accelerators referenced by the container.
+   * @default - No inference accelerators assigned.
+   */
+  readonly inferenceAcceleratorResources?: string[];
 }
 
 /**
@@ -386,6 +392,11 @@ export class ContainerDefinition extends CoreConstruct {
    */
   public readonly referencesSecretJsonField?: boolean;
 
+  /**
+   * The inference accelerators referenced by this container.
+   */
+  private readonly inferenceAcceleratorResources: string[] = [];
+
   /**
    * The configured container links
    */
@@ -443,6 +454,10 @@ export class ContainerDefinition extends CoreConstruct {
     if (props.portMappings) {
       this.addPortMappings(...props.portMappings);
     }
+
+    if (props.inferenceAcceleratorResources) {
+      this.addInferenceAcceleratorResource(...props.inferenceAcceleratorResources);
+    }
   }
 
   /**
@@ -516,6 +531,20 @@ export class ContainerDefinition extends CoreConstruct {
     }));
   }
 
+  /**
+   * This method adds one or more resources to the container.
+   */
+  public addInferenceAcceleratorResource(...inferenceAcceleratorResources: string[]) {
+    this.inferenceAcceleratorResources.push(...inferenceAcceleratorResources.map(resource => {
+      for (const inferenceAccelerator of this.taskDefinition.inferenceAccelerators) {
+        if (resource === inferenceAccelerator.deviceName) {
+          return resource;
+        }
+      }
+      throw new Error(`Resource value ${resource} in container definition doesn't match any inference accelerator device name in the task definition.`);
+    }));
+  }
+
   /**
    * This method adds one or more ulimits to the container.
    */
@@ -631,7 +660,8 @@ export class ContainerDefinition extends CoreConstruct {
       healthCheck: this.props.healthCheck && renderHealthCheck(this.props.healthCheck),
       links: cdk.Lazy.list({ produce: () => this.links }, { omitEmpty: true }),
       linuxParameters: this.linuxParameters && this.linuxParameters.renderLinuxParameters(),
-      resourceRequirements: (this.props.gpuCount !== undefined) ? renderResourceRequirements(this.props.gpuCount) : undefined,
+      resourceRequirements: (!this.props.gpuCount && this.inferenceAcceleratorResources.length == 0 ) ? undefined :
+        renderResourceRequirements(this.props.gpuCount, this.inferenceAcceleratorResources),
     };
   }
 }
@@ -742,12 +772,22 @@ function getHealthCheckCommand(hc: HealthCheck): string[] {
   return hcCommand.concat(cmd);
 }
 
-function renderResourceRequirements(gpuCount: number): CfnTaskDefinition.ResourceRequirementProperty[] | undefined {
-  if (gpuCount === 0) { return undefined; }
-  return [{
-    type: 'GPU',
-    value: gpuCount.toString(),
-  }];
+function renderResourceRequirements(gpuCount: number = 0, inferenceAcceleratorResources: string[] = []):
+CfnTaskDefinition.ResourceRequirementProperty[] | undefined {
+  const ret = [];
+  for (const resource of inferenceAcceleratorResources) {
+    ret.push({
+      type: 'InferenceAccelerator',
+      value: resource,
+    });
+  }
+  if (gpuCount > 0) {
+    ret.push({
+      type: 'GPU',
+      value: gpuCount.toString(),
+    });
+  }
+  return ret;
 }
 
 /**

packages/@aws-cdk/aws-ecs/lib/ec2/ec2-task-definition.ts

@@ -1,4 +1,5 @@
 import { Construct } from 'constructs';
+import { ImportedTaskDefinition } from '../base/_imported-task-definition';
 import {
   CommonTaskDefinitionAttributes,
   CommonTaskDefinitionProps,
@@ -8,9 +9,9 @@ import {
   NetworkMode,
   PidMode,
   TaskDefinition,
+  InferenceAccelerator,
 } from '../base/task-definition';
 import { PlacementConstraint } from '../placement';
-import { ImportedTaskDefinition } from '../base/_imported-task-definition';
 
 /**
  * The properties for a task definition run on an EC2 cluster.
@@ -51,6 +52,15 @@ export interface Ec2TaskDefinitionProps extends CommonTaskDefinitionProps {
    * @default - PidMode used by the task is not specified
    */
   readonly pidMode?: PidMode;
+
+  /**
+   * The inference accelerators to use for the containers in the task.
+   *
+   * Not supported in Fargate.
+   *
+   * @default - No inference accelerators.
+   */
+  readonly inferenceAccelerators?: InferenceAccelerator[];
 }
 
 /**
@@ -109,6 +119,7 @@ export class Ec2TaskDefinition extends TaskDefinition implements IEc2TaskDefinit
       placementConstraints: props.placementConstraints,
       ipcMode: props.ipcMode,
       pidMode: props.pidMode,
+      inferenceAccelerators: props.inferenceAccelerators,
     });
   }
 }