AWS Lambda Managed Instances で AZ 数による起動時の挙動の違いを確認してみた

import * as ec2 from "aws-cdk-lib/aws-ec2";
import { Construct } from "constructs";

export interface VpcConstructProps {
  maxAzs: number;
}

/**
 * VPC 実装
 */
export class VpcConstruct extends Construct {
  public readonly vpc: ec2.Vpc;
  constructor(scope: Construct, id: string, props: VpcConstructProps) {
    super(scope, id);

    this.vpc = new ec2.Vpc(this, "Default", {
      maxAzs: props.maxAzs,
      subnetConfiguration: [
        /**
         * NAT Gateway を配置するためのパブリックサブネット
         */
        {
          name: "Public",
          subnetType: ec2.SubnetType.PUBLIC,
        },

        /**
         * Lambda 関数を配置するためのプライベートサブネット
         */
        {
          name: "PrivateWithEgress",
          subnetType: ec2.SubnetType.PRIVATE_WITH_EGRESS,
        },
      ],
    });
  }
}

import * as cdk from "aws-cdk-lib";
import * as ec2 from "aws-cdk-lib/aws-ec2";
import * as lambda from "aws-cdk-lib/aws-lambda";
import * as lambda_nodejs from "aws-cdk-lib/aws-lambda-nodejs";
import { Construct } from "constructs";

import { VpcConstruct, VpcConstructProps } from "./constructs/vpc";

export class SampleStack extends cdk.Stack {
  constructor(
    scope: Construct,
    id: string,
    props: cdk.StackProps & VpcConstructProps
  ) {
    super(scope, id, props);

    /**
     * VPC 作成
     */
    const vpcConstruct = new VpcConstruct(this, "Vpc", {
      maxAzs: props.maxAzs,
    });
    const vpc = vpcConstruct.vpc;

    /**
     * セキュリティグループ作成
     *
     * MEMO: Capacity Provider 用に作成
     */
    const securityGroup = new ec2.SecurityGroup(this, "SecurityGroup", {
      vpc,
    });

    /**
     * Capacity Provider 作成
     *
     * MEMO: LMI のコア要素となるリソース
     */
    const capacityProvider = new lambda.CapacityProvider(
      this,
      "CapacityProvider",
      {
        subnets: vpc.selectSubnets({
          subnetType: ec2.SubnetType.PRIVATE_WITH_EGRESS,
        }).subnets,
        securityGroups: [securityGroup],
      }
    );

    /**
     * LMI 用 Lambda 関数作成
     */
    const lmiFunction = new lambda_nodejs.NodejsFunction(this, "LmiFunction", {
      entry: "src/handler.ts",
      runtime: lambda.Runtime.NODEJS_24_X, // Lambda Managed Instances では Node.js 18.x 以上が必須
      memorySize: 2048, // Lambda Managed Instances では 2048MB 以上が必須
      tracing: lambda.Tracing.ACTIVE, // コールドスタート発生状況の観測のために、AWS X-Ray を有効化
    });

    /**
     * Capacity Provider に Lambda 関数を追加
     */
    capacityProvider.addFunction(lmiFunction);
  }
}