Can karpenter provide something like PodDisruptionBudget?

[zwwhdls]

Description

What problem are you trying to solve?
JuiceFS users using JuiceFS CSI Driver in Kubernetes with karpenter have encountered the following problem:

I have pods on the same node that are depend on each other.

For example pod B depends on pod A and they are on the same node. And when B is deleted, A will be deleted by its controller(kubelet will trigger A's controller). But when A is deleted before B, B will not run well and result in Error.

But when I did a disruption in node. A and B are evicted in the same time, and B will cause Error which can not be accepted by consumers.

I tried two methods:

1. setup PodDisruptionBudget for A (which is proven to be effective in Kubernetes without karpenter), but karpenter ignored it, and evict both A and B.
2. set annotation karpenter.sh/do-not-disrupt in A , but karpenter do not trigger disruption anymore.

PDB will prevent A from be evicted during drain, and A will be deleted by its controller after B is deleted, so the entire drain can be successful. But it seems not work in karpenter.

Can karpenter provide something like PDB? It will help a lot in JuiceFS's case. Thanks!

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[jonathan-innis]

setup PodDisruptionBudget for A (which is proven to be effective in Kubernetes without karpenter), but karpenter ignored it, and evict both A and B

Can you show the PodDisruptionBudget that you are setting up? That statement leads me to believe that Karpenter doesn't respect PDBs but they should be considered during graceful disruption and in general during eviction

[zwwhdls]

@jonathan-innis The PodDisruptionBudget:

apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: jfs-pdb
  namespace: kube-system
spec:
  minAvailable: "100%"
  selector:
    matchLabels:
      app.kubernetes.io/name: juicefs-mount

[jonathan-innis]

And can you also share the pod manifests?