Chart version: 0.4.1
Api version: v1
App version: 1.0
Installs the a deployment that overprovisions the cluster
Chart Type
Set me up:
helm repo add center
Install Chart:
helm install cluster-overprovisioner center/stable/cluster-overprovisioner
Versions (0)

DEPRECATED This repository has moved

With upcoming deprecation of helm/charts repository, the cluster-overprovisioner Helm Chart has moved to Delivery Hero’s Helm Repository:

You can use this new Helm repository by doing:

helm repo add deliveryhero
helm search repo deliveryhero

You can now use deliveryhero/cluster-overprovisioner instead of stable/cluster-overprovisioner in all your Helm commands, e.g.:

# New installation
helm install --name <RELEASE_NAME> deliveryhero/cluster-overprovisioner
# Upgrade existing installation
helm upgrade --name <RELEASE_NAME> deliveryhero/cluster-overprovisioner

Cluster overprovisioner

This chart provide a buffer for cluster autoscaling to allow overprovisioning of cluster nodes. This is desired when you have work loads that need to scale up quickly without waiting for the new cluster nodes to be created and join the cluster.

It works but creating a deployment that creates pods of a lower than default PriorityClass. These pods request resources from the cluster but don’t actually consume any resources. These pods are then evicted allowing other normal pods are created while also triggering a scale-up by the cluster-autoscaler.

This approach is the current recommended method to achieve overprovisioning.


  • Kubernetes 1.11+ with Beta APIs enabled or 1.8-1.10 with alpha APIs enabled
  • Pod priority and preemption enabled in your cluster. Pod priority and preemption is enabled by default in Kubernetes >= 1.11.
  • cluster-autoscaler installed in your cluster with --expendable-pods-priority-cutoff=-10 . Priority cutoff has a default of -10 in cluster-autoscaler >= 1.12.

Installing the Chart

To install the chart with the release name my-release and default configuration:

$ helm install --name my-release stable/cluster-overprovisioner

Uninstalling the Chart

To delete the chart:

$ helm delete my-release


Some thought or experimentation is required to set deployment.resources and deployment.replicaCount correctly. Aspects such as cluster size, costs and size of buffer required should be considered.

The following table lists the configurable parameters for this chart and their default values.

Parameter Description Default
podSecurityContext Pod security context object {} Name of the overprovision priorityClass overprovision
priorityClassOverprovision.value Priority value of the overprovision priorityClass -1
priorityClassDefault.enabled If true, enable default priorityClass true Name of the default priorityClass default
priorityClassDefault.value Priority value of the default priorityClass 0
image.repository Image repository
image.tag Image tag 3.1
image.pullSecrets Image pull secrets []
image.pullPolicy Container pull policy IfNotPresent
fullnameOverride Override the fullname of the chart nil
nameOverride Override the name of the chart nil
deployments Define optional additional deployments []
deployments[].name Name for additional deployments (will be added as label cluster-over-provisioner-name, so you can match it with affinity rules)
deployments[].replicaCount Number of replicas 1
deployments[].annotations Annotations to add to the deployment {}
deployments[].resources Resources for the overprovision pods {}
deployments[].affinity Map of node/pod affinities {}
deployments[].nodeSelector Node labels for pod assignment {}
deployments[].tolerations Optional deployment tolerations []
deployments[].labels Optional labels tolerations {}

Specify each parameter using the --set key=value[,key=value] argument to helm install or provide a YAML file containing the values for the above parameters:

$ helm install --name my-release stable/cluster-overprovisioner --values values.yaml