Cluster autoscaler should remove unused "node-autoprovisioning-enabled" flag and the related metrics

[elmiko]

Which component are you using?:

cluster-autoscaler

What version of the component are you using?:

Component version: 1.28.0

What k8s version are you using (kubectl version)?:

1.28.2

What environment is this in?:

this affects all environments

What did you expect to happen?:

I expect the node-autoprovisioning-enabled flag to change the behavior of the cluster-autoscaler when it is set or unset.

What happened instead?:

Changing this flag has no effect as it is essentially a left over from an earlier version of the autoscaler.

How to reproduce it (as minimally and precisely as possible):

Run the autoscaler with --node-autoprovisioning-enabled and without, there is no change in the behavior of the autoscaler.

Anything else we need to know?:

This issue was discussed during the SIG meeting from 2023-10-23, and agree that removal is safe and the function is no longer in use.

The node autoprovisioning metrics should also be removed as part of this effort, see https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/metrics/metrics.go#L352-L375

/good-first-issue
/help

[k8s-ci-robot]

@elmiko:
This request has been marked as suitable for new contributors.

Guidelines

Please ensure that the issue body includes answers to the following questions:

• Why are we solving this issue?
• To address this issue, are there any code changes? If there are code changes, what needs to be done in the code and what places can the assignee treat as reference points?
• Does this issue have zero to low barrier of entry?
• How can the assignee reach out to you for help?

For more details on the requirements of such an issue, please see here and ensure that they are met.

If this request no longer meets these requirements, the label can be removed
by commenting with the /remove-good-first-issue command.

In response to this:

Which component are you using?:

cluster-autoscaler

What version of the component are you using?:

Component version: 1.28.0

What k8s version are you using (kubectl version)?:

1.28.2

What environment is this in?:

this affects all environments

What did you expect to happen?:

I expect the node-autoprovisioning-enabled flag to change the behavior of the cluster-autoscaler when it is set or unset.

What happened instead?:

Changing this flag has no effect as it is essentially a left over from an earlier version of the autoscaler.

How to reproduce it (as minimally and precisely as possible):

Run the autoscaler with --node-autoprovisioning-enabled and without, there is no change in the behavior of the autoscaler.

Anything else we need to know?:

This issue was discussed during the SIG meeting from 2023-10-23, and agree that removal is safe and the function is no longer in use.

The node autoprovisioning metrics should also be removed as part of this effort, see https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/metrics/metrics.go#L352-L375

/good-first-issue
/help

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[elmiko]

if any new contributors are interested in picking this issue up, please feel free to reach out on slack (@elmiko), i'm happy to give guidance.

[prashantrewar]

I am a beginner. I want to do this issue

[elmiko]

great @prashantrewar , happy to help.

in my initial analysis, we currently have 2 command line flags which appear to no longer be in use: --node-autoprovisioning-enabled, and --max-autoprovisioned-node-group-count.

the flags are created here: https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/main.go#L193-L194

there are a few task which need to be done:

1. investigate these flags to ensure they are not being used in the production code (not tests)
2. investigate the related metics to ensure that they are not used.
3. if you can confirm they are not being used, we should remove nearly all the code for the flags and metrics.
4. we need to keep the command line flags available, but they should print a warning that they are deprecated.

in the SIG meeting we agreed that we should probably follow the deprecation guidelines for these flags. this means that we need to continue to accept the flags for 12 months or 2 releases. this is why we want to print a warning when the flags are used, but otherwise remove the code behind them as it appears to do nothing.

when this is resolved we need to make sure that the release notes contain a message about the deprecations, that will come towards the end when you are merging patches.

please let me know if you would like more details on any of those points, and thanks again for volunteering!

[elmiko]

/assign @prashantrewar

[Shubham82]

/triage accepted

[Vandit1604]

This issue can be closed. Fixed by #6246

[Shubham82]

Closing this issue as it is resolved by PR #6246.

[Shubham82]

/close