Merge pull request #8652 from iamzili/add-warning-pod-level-stanza

docs: Document VPA incompatibility with pod-level resources stanza

Author: k8s-ci-robot

vertical-pod-autoscaler/README.md

@@ -45,6 +45,11 @@ The Vertical Pod Autoscaler consists of three parts. The recommender, updater an
 
 You can also read about the [features](./docs/features.md) and [known limitations](./docs/known-limitations.md) of the VPA.
 
+> [!IMPORTANT]
+> At the moment, VPA is not compatible with workloads that define pod-level `resources` stanzas. Work has started to add pod-level resources support for VPA, for more details see [AEP-7571](https://github.com/kubernetes/autoscaler/pull/8586). Users of VPA may encounter the following issues if they enable VPA for a workload with a pod-level resources stanza defined:
+> * When the admission-controller tries to set a container-level limit higher than the pod-level limit, the operation is prohibited, and the pod will not be created.
+> * When the admission-controller tries to set the newly recommended container-level requests, their total value cannot exceed the pod-level request or limit. For example, if the pod-level memory request is 100Mi, but the newly recommended total of container-level requests is 250Mi, the pod will fail to be created.
+
 ## Related links
 
 - [Design proposal](https://github.com/kubernetes/design-proposals-archive/blob/main/autoscaling/vertical-pod-autoscaler.md)