placeholder: enforce system reserved memory

[ffromani]

Enhancement Description

• One-line enhancement description: prevent burstable and best effort pods to consume system reserved memory
• Kubernetes Enhancement Proposal: TBD
• Discussion Link: TBD
• PRs by stage and milestone:
  • Alpha - v1.xx
    • KEP (k/enhancements) update PR(s):
    • Code (k/k) update PR(s):
    • Docs (k/website) update PR(s):

[ffromani]

Similarly to #4540 , we should prevent burstable and best effort pods to consume memory reserved for system components. Conceptually, a way to fix this can be to set the memory max for the root slices.

This functionality should belog to the same component which owns the memory allocation, thus kubelet and specifically the memory manager.

[ffromani]

/sig node

[ffromani]

cc @MarSik