vpa_butler

README

vpa_butler

The vpa_butler is a Kubernetes controller that serves instances of the VerticalPodAutoscaler CRD for deployments, statefulsets and daemonsets, so you don't have to create them.

Concept

The butler regularly reconciles all deployments, statefulsets and daemonsets in a cluster. If it comes across one that is not targeted by a VerticalPodAutoscaler resource, it will create a VPA resource to get predictions for CPU and memory. To opt-out of the vpa_butler, deploy a hand-crafted VPA instance along with the payload. The vpa_butler will clean-up served VPA instances.

The served VPA is constructed in the following way:

• The VPA is created in the same namespace as the targeted resource and named like the targeted resource adding the suffix -deployment, -statefulset, -daemonset.
• The update mode is set to the value of the --default-vpa-update-mode CLI flag.
• The minAllowed recommendation is set to the values of the --default-min-allowed-cpu and --default-min-allowed-memory CLI flags.
• The maxAllowed recommendation is set to the percentage of capacity specified by the --capacity-percent CLI flag of the largest viable node regarding memory. The vpa_butler determines the viable nodes by considering, where pods of the payload could be scheduled repsecting NodeName, NodeAffinity, NodeUnscheduable and TaintToleration. These values are updated every 30 seconds.