cluster-proportional-autoscaler VS vcluster

The Cluster Proportional Autoscaler (CPA) is a horizontal pod autoscaler that scales replicas based on the number of nodes in the cluster. Unlike other autoscalers, it does not rely on the Metrics API and does not require the Metrics Server. Additionally, unlike other autoscalers we saw, a CPA is not scaled with a Kubernetes resource but instead uses flags to identify target workloads and a ConfigMap for scaling configuration. The following diagram illustrates the components of the CPA:

Namespacing each environment would give you isolation, depending on how your service discovery works within the environment. You could consider the horizontal proportional autoscaler (or maybe KEDA) and hook it up to a metric for the queue depth. https://github.com/kubernetes-sigs/cluster-proportional-autoscaler

If we want to configure dynamic overprovisioning of a cluster (e.g. 20% of resources in the cluster) then we need to use Horizontal Cluster Proportional Autoscaler.

Kubernetes? You mean the container orchestration system where they forgot to add Multi-tenancy? And no namespaces are not Multi-tenancy...

https://www.vcluster.com/

Whats the difference between this and vcluster (https://github.com/loft-sh/vcluster)?

Yep, as we see it they compliment each other quite well. DevPod takes your workspace to the cloud and DevSpace let's you develop against your Kubernetes cluster - potentially the same one you used to start your workspace.

Internally we use both in our development setup, spinning up remote workspaces using DevPod, installing DevSpace and kind into the devcontainer, then using DevSpace to develop against the cluster. See the vcluster setup[1] as an example

[1]https://github.com/loft-sh/vcluster/tree/main/.devcontainer

The tenants are internal dev teams so yeah maybe not. I was considering multi-tenanting different environments isolated at the kube layer with vCluster and have the vCluster pods running in Kata containers giving maximum isolation but still having a single management cluster. Ideally also avoiding the need to buy a second set of hardware for a dev environment

Vcluster

Looks interesting. How does this solution compare to vcluster?

sounds like the best option for you , is a tool called VCluster by loft ( https://www.vcluster.com/) , this way you can install as many k8s cluster as you want in the same k8s host cluster , those cluster share workers nodes and networking, but each has a separated "api server" , so it looks like you have a dedicated cluster with their own namespaces and tools . take a look at the docs to get a better understanding and how they work.

We're about to run a PoC with vcluster for isolated sandboxes, this might be relevant to you too

I think namespaces, RBAC and network policies are sufficient to partition users from the same organisation. I would investigate the use of vcluster ig you want to give your users even more isolation and capability (such as installing CRDs)

Depends on the use case. Namespaces provides soft isolation (so it means they share same Apiserver, PV's and global resources such as CRD's), but can be restricted with network policies. So it means, there's still potential in breaking other namespaces if you change PV's or CRD's which are used by other namespaces. Multi-Cluster solution can provide full isolation, but its also really expensive in resource consumption and maintenance/management effort. If namespaced-isolation isnt enough for your use case, you can consider vclusters (https://www.vcluster.com/)