http-add-on VS metrics-server

KEDA ships with an HTTP add-on to enable HTTP scaling.

KEDA has a special scaler that creates an HTTP proxy that measures and buffers requests before they reach the app.

I am a core maintainer on the KEDA HTTP Addon project (https://github.com/kedacore/http-add-on). It's 100% written in Go and we are a small group looking for additional contributors. I believe there are interesting challenges ahead of us that will be enjoyable to solve.

If you're interested, please reach out. My username here is the same as my username on the Gophers and Kubernetes slack groups.

(You're of course welcome to just go pick up an issue in the repo if you'd prefer)

The KEDA HTTP Addon project contains three major components: the operator, scaler and interceptor.

Hacking on the KEDA HTTP Addon, I found myself having to do something familiar:

First, we need to finish the minimal infrastructure. The components and supporting artifacts (Helm charts, CI scripts, etc...) are being built in PR #2, and once we have them completed, we will merge it [5]. Second, we need to establish a roadmap. We're beginning to outline it now and will finish it shortly after merging.

Before deploying anything into this namespace, it’s important first to verify that the metrics server is deployed and configured in your cluster. This metrics server is part of how Kubernetes implements autoscaling rules. Check whether it’s installed by running:

Metrics Server is a Kubernetes addon that collects CPU and memory resource utilization information at the Node and Pod level. It's a lightweight, single-cluster, Kubernetes-only alternative to more complex monitoring solutions like Prometheus.

(kubespray-venv) kube-master1:~# curl -LO https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml nano components.yaml

The last one is mostly an observability stack with Prometheus, Metric server, and Prometheus adapter to have excellent insights into what is happening on the cluster. You can reuse the same stack for autoscaling by repurposing all the data collected for monitoring.

and the Metrics Server.

Metrics-server is installed by default on OVH, and has to be installed manually on AWS/EKS cluster.

I have also installed metrics-server (though not sure whether that was required or not) using the following statement:kubectl apply -f https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.3.6/components.yaml

For #2: There are MANY solutions but the simplest and easiest is https://github.com/kubernetes-sigs/metrics-server and then you can use kubectl top to view pods resource usage. If you want fancy graphs, long retention, alerting, analysis, etc. of resource metrics.. then you need to use something like new relic, data dog, or something open source but much more complex like prometheus/thanos/grafana.. or a managed SaaS version of those open source tools... also some k8s platforms like AWS, Spot.io, GKE, OpenShift, may have this stuff built in or turnkey

It's an autoscaler with a metrics server (so I don't need to install 2 different tools).