Support vpa

[jiangpengcheng]

Fixes #462

Motivation

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Modifications

Support VPA(vertical pod autoscaler)

Verifying this change

• [x] Make sure that the change passes the CI checks.

• [x] This change added tests and can be verified as follows:

  • *Added integration tests for function with VPA enabled

Documentation

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[jiangpengcheng]

for different vendors:

1. openshift:

   needs to be installed manually: https://docs.openshift.com/container-platform/4.11/nodes/pods/nodes-pods-vertical-autoscaler.html#nodes-pods-vertical-autoscaler-install_nodes-pods-vertical-autoscaler

2. GKE:

   needs to be enabled manually: https://cloud.google.com/kubernetes-engine/docs/concepts/verticalpodautoscaler

3. AWS:

   needs to install VPA operators manually: https://docs.aws.amazon.com/eks/latest/userguide/vertical-pod-autoscaler.html

4. Azure:

   needs to enable vpa when creating cluster: https://learn.microsoft.com/en-us/azure/aks/vertical-pod-autoscaler#deploy-upgrade-or-disable-vpa-on-a-cluster

for all of these vendors, I think we can use this pr's helm dependencies to install VPA operators, it should work as expected, but I didn't test that

[jiangpengcheng]

and about the JVM limits, there is an issue talking about it: https://github.com/kubernetes/autoscaler/issues/5029

it looks like someone is using VPA on jvm pod for memory requests spec(not including limit)

[freeznet]

ping @fantapsody @nlu90 please help to review this when you have time, thanks.

[jiangpengcheng]

@jiangpengcheng There are conflicts that need to be resolved

already resolved, it's ready to review, thanks