This page explains how Google Kubernetes Engine dynamically allocates resources for certain add-ons.
Add-on autoscaling
GKE uses add-on resizer to scale the metrics-server add-on and the heapster add-on. The add-on resizer scales the resource requests and resource limits of its managed containers in proportion to the number of nodes in the cluster. using the following formula:
| Kubernetes version | Formula |
|---|---|
| 1.11.x and lower | \( R=b+m \times \max(n,16) \) |
| 1.12.x and higher | \( R=b+m \times \max(n,5) \) |
Where the resource request or limit, \(R\), is equal to the base request/limit, \(b\), plus the marginal resource requirement, \(m\), times the node count of the cluster, \(n\).
If the cluster has 5 or fewer nodes (16 or fewer nodes, for Kubernetes 1.11.x and lower), add-on resizer will assign resources as though the cluster had 5 nodes.