AWS Firecracker vs Docker: What are the differences?

Introduction

AWS Firecracker and Docker are both containerization technologies that allow for the efficient deployment and management of applications. However, there are several key differences between these two platforms.

1. Performance: AWS Firecracker is designed for lightweight, single-purpose virtual machines (microVMs), whereas Docker is a containerization platform. Firecracker provides a secure and highly efficient environment for running workloads, with minimal overhead. On the other hand, Docker containers share the host OS kernel, which can introduce some performance overhead.

2. Security: Firecracker provides strong isolation between microVMs to enhance security. Each microVM is run in its own lightweight kernel and has a minimal attack surface. Docker, although it provides some level of isolation, shares the host OS kernel, making it potentially more vulnerable to container escapes. However, Docker provides features like namespaces and container security options to mitigate security risks.

3. Start Time: Firecracker has extremely fast startup times, allowing for rapid scaling and efficient resource utilization. It can launch new microVMs in just a few milliseconds. Docker containers, on the other hand, typically take several seconds to start up. Although Docker has made improvements in startup time, Firecracker is still faster when it comes to launching new instances.

4. Footprint: Firecracker has a smaller footprint compared to Docker. It is designed to provide a minimalist virtualization environment with a small memory and disk footprint. Docker, on the other hand, requires the installation of the Docker daemon and additional container images, resulting in a larger overall footprint.

5. Elasticity: Firecracker is built to be highly elastic, allowing for efficient scaling and handling of bursty workloads. It can quickly launch and terminate microVMs based on demand, making it suitable for auto-scaling scenarios. Docker also supports scaling, but it may have slightly higher startup times and overhead compared to Firecracker.

6. Tooling and Ecosystem: Docker has a mature and extensive ecosystem with a wide range of tools and services that support container management, orchestration, and deployment. It has a large community and a rich set of pre-built container images available. Firecracker, being a relatively newer technology, has a smaller ecosystem and fewer tooling options compared to Docker.

In Summary, AWS Firecracker is a lightweight virtualization technology designed for microVMs, providing high performance, security, and scalability. Docker, on the other hand, is a containerization platform focused on providing a broader set of features and a mature ecosystem for managing and deploying containerized applications.