EC2 & Lambda

Virtual servers and serverless compute

EC2 (Elastic Compute Cloud)

EC2 provides resizable virtual machines in the cloud. You choose instance type (CPU, memory), AMI (OS image), and storage. You manage the OS, runtime, and application.

• Instance Types: t3 (burstable general), m6i (general), c6i (compute), r6i (memory), p4 (GPU)
• Pricing: On-Demand (pay per hour), Reserved (1-3yr commitment, up to 72% off), Spot (up to 90% off, can be interrupted)
• Auto Scaling: automatically adjust instance count based on CPU, memory, or custom metrics
• AMI: Amazon Machine Image — snapshot of OS + pre-installed software

Lambda (Serverless)

Lambda runs code without provisioning servers. You pay only for compute time consumed. Functions scale automatically from zero to thousands of concurrent executions.

// Lambda Function
// handler.ts
export const handler = async (event: APIGatewayProxyEvent) => {
  const body = JSON.parse(event.body || '{}');

  // Process the request
  const result = await processOrder(body);

  return {
    statusCode: 200,
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(result),
  };
};

// Limitations:
// - 15 min max execution time
// - 10 GB max memory
// - 250 MB deployment package (50 MB zipped)
// - Cold starts: 100ms-2s for first invocation

ECS & EKS

• ECS (Elastic Container Service) — AWS-native container orchestration. Simpler than K8s.
• EKS (Elastic Kubernetes Service) — managed Kubernetes. Full K8s compatibility.
• Fargate — serverless compute for ECS/EKS. No EC2 instances to manage.
• Use ECS for simpler deployments, EKS for K8s ecosystem compatibility.