Question 1

What is the main difference between AWS Fargate and AWS Lambda?

Accepted Answer

The main difference is the execution model. AWS Lambda runs event-driven functions and charges per request and execution time. AWS Fargate runs containers and charges for allocated CPU and memory while tasks are running.

Question 2

Is AWS Lambda considered Function-as-a-Service (FaaS)?

Accepted Answer

Yes. AWS Lambda is a Function-as-a-Service (FaaS) offering. It executes individual functions in response to events without requiring server or infrastructure management. AWS Fargate is not Faas. It is a serverless compute engine for containers, often categorized as Container-as-a-Service (CaaS).

Question 3

Can AWS Lambda run long-running workloads?

Accepted Answer

No. AWS Lambda has a maximum execution time of 15 minutes per invocation. Because of this limit, Lambda is not suitable for long-running or continuously running processes. AWS Fargate is the better choice for workloads that need to run for hours or indefinitely.

Question 4

How do AWS Fargate and AWS Lambda scale?

Accepted Answer

AWS Lambda scales automatically in response to events and can scale down to zero when idle. This makes it ideal for unpredictable or bursty traffic. AWS Fargate scales by adding or removing container tasks based on demand. Tasks remain running, which avoids cold-start latency but does not scale to zero by default. Related reads:  Cloud Infrastructure Scaling And How It Optimizes Costs And Time   AWS Auto Scaling 101: What It Is And Tips For Success   Scaling Kubernetes On A Budget: AKS Vs. EKS Cost-Savings   Horizontal Vs. Vertical Scaling: Which Should You Choose?

Question 5

Which is cheaper: AWS Lambda or AWS Fargate?

Accepted Answer

Neither service is universally cheaper; it depends on workload behavior. AWS Lambda is more cost-effective for spiky, infrequent, or event-driven workloads because you pay only when code runs. AWS Fargate is often more predictable and cost-efficient for steady, long-running services because costs track allocated CPU and memory.

Question 6

Does AWS Fargate require Amazon ECS or Amazon EKS?

Accepted Answer

Yes. AWS Fargate runs as a launch type within Amazon ECS or Amazon EKS. It does not run independently. AWS manages the underlying compute infrastructure, while ECS or EKS handles orchestration.

Question 7

What are the security differences between AWS Fargate and AWS Lambda?

Accepted Answer

AWS Lambda assigns IAM roles at the function level and runs each function in an isolated execution environment. AWS Fargate assigns IAM roles to tasks or pods, with each task running in its own isolated compute environment without shared CPU, memory, kernel, or networking resources.

Question 8

Which service is better for event-driven architectures?

Accepted Answer

AWS Lambda is the better fit for event-driven architecture workloads. It integrates natively with AWS services such as Amazon S3, EventBridge, and API Gateway and executes code automatically when events occur. AWS Fargate is better suited for services that continuously process work rather than react to discrete events.

Question 9

Can AWS Lambda and AWS Fargate be used together?

Accepted Answer

Yes. Modern AWS architectures use both services together. A common pattern is to use AWS Lambda for event ingestion, orchestration, or lightweight processing. AWS Fargate for long-running or resource-intensive container workloads.

Question 10

When should I choose AWS Fargate over AWS Lambda?

Accepted Answer

Choose AWS Fargate when you need :  Long-running workloads   Container-based applications   Explicit CPU and memory control   Kubernetes or ECS compatibility  Choose AWS Lambda when you need:  Event-driven execution   Automatic scaling to zero   Minimal operational overhead

The AI Cost Optimization Playbook

Why Finance Caps What It Can’t See