Vertical Pod Autoscaler

Similar to HPA, it monitors resources, and increases resources on the pod if required. It is not inbuilt, it needs to be downloaded and applied.

It has three components -

1. Admission controller - applies the changes recommender suggests
2. Updater - evicts the pods if needed based on recommender
3. Recommender - does not modify anything, just provides recommendations.

updateMode controls how this happens.

1. Off - only recommendations, no changes
2. Initial - only changes pods on creation
3. Recreate - Evicts pods if usage goes beyond range.
4. InPlaceOrRecreate - Tries to update without restarting a pod - future feature.