fission VS enhancements

Fission

This is where I see K8S coming in – teachers can provide dev deployments that are setup for students to learn. Teachers can also provide containers that run automated tests against the student containers for assessment! Plus, we can smooth over some of the git workflow stuff for the ripest of beginners; we can integrate with github to sync their work on our platform to repositories on their github account, so that they can really take ownership of the work they do on the platform. Last, students can graduate their work from development into production very easily, since we can take the base images + student diffs, build a new "prod" image for the student. We can run students' prod work on "serverless" K8S frameworks like fission or OpenFaas to be able to host many low-traffic "production" apps at the same time.

I use https://fission.io/ on Kubernetes to emulate AWS Lambda + API Gateway to run Python functions. I use their YAML Spec functionality to deploy functions. It works well for my use case.

After doing a lot of research, I ended up settling on the Fission.io framework to support this project. Fission is an open-source Serverless framework running in kubernetes. Think AWS Lambdas, but we are in control of every part of the infrastructure. Kubernetes gives us the power to define the environments the containers will be executed in, and any other resources they need. This gives us the control we need to be able to create our very own environment for executing arbitrary JavaScript through the V8 engine. Each function can be isolated as much as we need to and Fission is really great at giving us the ability to quickly create multiple environments.

Nope. I was using https://fission.io/

There are a lot of FaaS service offerings out there namely Lambda, Azure Functions, Google Cloud Functions to name a few. While these offerings run on their respective clouds, there are services like Fission that are open source and allow you to deploy and execute functions on Kubernetes clusters irrespective of where they reside.

Fission

It's super slow (20-50 rps), please try this instead : https://github.com/fission/fission (few hundreds to few thousands rps)

0 is not the request we've defined. And that makes sense. Memory QoS has been in alpha since Kubernetes 1.22 (August 2021) and according to the KEP data was still in alpha as of 1.27.

Note: There's actually a Structured Authentication Config established via KEP-3331. It's in v1.28 as a feature flag gated option and removes the limitation of only having one OIDC provider. I may look into doing an article on it, but for now I'll deal with the issue in a manner that should work even with a bit older versions versions of Kubernetes.

Kubernetes supports a skew policy of n+2 between API server and kubelet. This means if your CP and DP are both on 1.20, you could upgrade your control plane twice (1.20 -> 1.21 -> 1.22) before you need to upgrade your data plane. And when it comes time to upgrade your data plane you can jump from 1.20 to 1.22 to minimize update churn. In the future, this skew will be opened to n+3 https://github.com/kubernetes/enhancements/tree/master/keps/sig-architecture/3935-oldest-node-newest-control-plane

The KEP (Kubernetes Enhancement Proposal) is linked to in the PR [1]. From the summary:

> Sidecar containers are a new type of containers that start among the Init containers, run through the lifecycle of the Pod and don’t block pod termination. Kubelet makes a best effort to keep them alive and running while other containers are running.

[1] https://github.com/kubernetes/enhancements/tree/master/keps/...

This is where the new feature of mutable scheduling directives for jobs comes into play. This feature enables the updating of a job's scheduling directives before it begins. Essentially, it allows custom queue controllers to influence pod placement without needing to directly handle the assignment of pods to nodes themselves. To learn more about this check out the Kubernetes Enhancement Proposal 2926.

What your asking is a (vanilla) Kubernetes non-goal, others have mentioned fluxcd and other add ons that provide primitives for dependency aware deployments. The problem space is so large, that it's unreasonable to to address these concerns in Kubernetes itself, instead, make it extensible... Look at this KEP for example: https://github.com/kubernetes/enhancements/issues/753 Sidecar containers have existed, and been named as such since WAY before that KEP's inception, defining what these things should and shouldn't do is largely arbitrary. Aka: your use-case is niche, if you don't like the behavior, use flux or argo, or write something yourself.

If further interested, I may recommend checking out the KEP. I love how they document the decision making, and all these edge cases :).

See https://kubernetes.io/docs/reference/kubectl/conventions/#subresources and https://github.com/kubernetes/enhancements/issues/2590