AWS Firecracker vs AWS Lambda: What are the differences?

Introduction

In this Markdown code, we will outline the key differences between AWS Firecracker and AWS Lambda, two services provided by Amazon Web Services (AWS) for different purposes.

1. Scalability: AWS Firecracker is designed to run containerized workloads securely and efficiently with minimal overhead. It provides excellent performance and scalability, enabling the launching of thousands of microVMs in seconds. On the other hand, AWS Lambda is an event-driven computing service that automatically scales applications in response to incoming requests. It allows developers to run code without provisioning or managing servers, providing effortless scalability.

2. Execution Environment: Firecracker provides a slim, lightweight hypervisor that allows running applications within isolated virtual machines known as microVMs. These microVMs provide enhanced security and resource isolation. In contrast, Lambda runs code in a fully managed environment, automatically handling capacity provisioning, patching, and OS maintenance. Developers can focus solely on writing code without worrying about the underlying infrastructure.

3. Pricing Model: AWS Firecracker is not a pay-per-use service but rather offered as an open-source project. It can be utilized to build and manage container-based solutions without any additional cost, other than the infrastructure costs associated with running the microVMs on AWS. On the other hand, AWS Lambda pricing is based on the number of requests and duration of the code execution. Users pay only for the compute time consumed, with no upfront costs or any fees when the code is not running.

4. Instance Execution Time: When using Firecracker, the instance startup time is relatively faster due to its lightweight nature and efficient boot process. MicroVMs launch almost instantaneously, allowing for rapid scaling and spawning of new instances. In contrast, AWS Lambda takes a few milliseconds to initialize the execution environment, known as "cold start," when the function is triggered for the first time. Subsequent invocations benefit from "warm start" and execute much faster.

5. Customization and Interface: Firecracker offers customization options as an open-source project, allowing users to tailor the implementation to their specific requirements. It provides a set of APIs for developers to interact with and integrate into their systems. Lambda, however, offers a higher level of abstraction and simplification, abstracting away the infrastructure details. It provides a user-friendly interface and supports multiple programming languages, enabling developers to focus on code functionality rather than infrastructure management.

6. Use Cases: Firecracker is well-suited for running serverless workloads, containerized microservices, and isolated environments where security and resource efficiency are major concerns. It enables running containers at a much lower overhead compared to traditional virtualization approaches. On the other hand, Lambda is ideal for event-driven scenarios, where code is executed in response to events or triggers such as API calls, file uploads, database changes, etc. It excels in handling small, short-lived functions effectively and presents an efficient solution for serverless architectures.

In summary, AWS Firecracker is focused on providing a lightweight and highly scalable platform for containerized workloads, emphasizing speed, security, and customization options. AWS Lambda, on the other hand, offers a fully managed compute service that scales applications automatically, simplifying deployment and maintenance efforts for event-driven functions in a serverless environment while abstracting away the underlying infrastructure complexities.