Add support for cronjobs in VPA

[bskiba]

Fixes #1790

[bskiba]

@schylek

[schylek]

In general /lgtm. Do you think Cron Jobs are worth adding e2e test?

[bskiba]

I was thinking about adding e2e. Currently we only have almost all tests with VPA on Deployment, the only ones where we exercise different controllers is updater (Evicts pods in ...). I came to a conclusion that it makes little sense to evict pods from a CronJob.
However it would be nice to have a "VPA provides recommendations" scenario for all the known controllers.

[bskiba]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: bskiba

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• vertical-pod-autoscaler/OWNERS [bskiba]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[mcfedr]

Would it be possible for the VPA to make its recommendations so that the next time the job is run it uses the recommendations?

[bskiba]

Yes, once this releases, if you set VPA on CronJob and updateMode: Initial, each new launched Job will get request based on recommendations calculated from previous jobs usage.

Note, this will not work well with short lived jobs (<1minute).

[johanneswuerbach]

@bskiba is there any timeline when this is going to be released?