Today, Red Hat released v2.19.1 of Custom Metrics AutoScaler. Based on KEDA, the optional operator increases or decreases the number of Pods, custom resource, or Job based on custom metrics; it's not only about CPU and memory. You can control your applications to control usage.

To get started:

1. On OpenShift Container Platform web console, click Ecosystem > Installed Operators.
2. Select Custom Metrics Autoscaler.
3. On the Operator Details page, click the KedaController tab.
4. On the KedaController tab, click Create KedaController and edit the file.

apiVersion: keda.sh/v1alpha1
kind: KedaController
metadata:
  name: keda
  namespace: openshift-keda
spec:
  metricsServer:
    logLevel: "0"
  operator:
    logEncoder: console
    logLevel: info
  serviceAccount: {}
  watchNamespace: ""

You can integrate with Kafka

helm repo add strimzi https://strimzi.io/charts/
helm repo update
helm upgrade --install --namespace strimzi --wait strimzi strimzi/strimzi-kafka-operator --version 0.47.0 --set watchAnyNamespace=true

Good luck...

References

1. Red Hat OpenShift Docs: Chapter 3. Automatically scaling pods with the Custom Metrics Autoscaler Operator
2. Red Hat Developer: Custom Metrics Autoscaler on OpenShift
3. keda.sh: Kubernetes Event-driven Autoscaling
4. Custom Metrics Autoscaler Operator v2.19.1 supports IBM Power