Knative vs OpenFaaS: What are the differences?

Knative and OpenFaaS are two popular frameworks in the serverless computing space. Let's explore the key differences between them.

1. Programming Language Support: Knative supports multiple programming languages, including Java, Node.js, Go, PHP, and Ruby. On the other hand, OpenFaaS primarily focuses on supporting Docker containers, allowing developers to use any programming language or framework.

2. Runtime Environment: Knative is built on Kubernetes and leverages its orchestration capabilities to manage scalable serverless workloads. OpenFaaS can also be deployed on Kubernetes but also offers support for alternative runtimes like Docker Swarm, Nomad, and even standalone mode without any orchestration layer.

3. Scaling Mechanism: Knative provides auto-scaling capabilities out-of-the-box, automatically scaling up or down based on incoming requests or defined metrics. OpenFaaS, on the other hand, relies on the underlying container orchestrator's scaling mechanisms, requiring manual configuration for scaling.

4. Ecosystem and Community: Knative has gained significant adoption and is backed by major industry players like Google, IBM, and Red Hat. It benefits from a larger ecosystem and a supportive community, with a growing number of contributors and integrations. OpenFaaS also has a strong community following and contributions, but it may have a smaller ecosystem compared to Knative.

5. Event-Driven Capabilities: Knative provides native support for event-driven architectures, allowing developers to easily build and run event-driven applications. OpenFaaS, while capable of handling events, does not have the same level of native support for event-driven architectures.

6. Resource Utilization: Knative optimizes resource utilization by scaling to zero when there are no incoming requests, reducing costs and improving efficiency. OpenFaaS, by default, keeps replicas running even during idle periods, which may result in higher resource consumption and costs.

In summary, Knative offers broader programming language support, leverages Kubernetes for orchestration, provides extensive auto-scaling and event-driven capabilities, and enjoys a larger ecosystem and community support. OpenFaaS, on the other hand, has a flexible runtime environment, supports any programming language through Docker containers, and may be a better fit for existing container orchestration setups.