perf: Add flag to disable costly metrics controllers

[DerekFrank]

Fixes #N/A

Description

Metrics controllers can cause metric scrape timeouts at scale, this adds an optional feature flag to disable them

How was this change tested?

make presubmit

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: DerekFrank
Once this PR has been reviewed and has the lgtm label, please assign tzneal for approval. For more information see the Code Review Process.

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

Needs approval from an approver in each of these files:

• OWNERS

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

[k8s-ci-robot]

Hi @DerekFrank. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

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-sigs/prow repository.

[coveralls]

Pull Request Test Coverage Report for Build 16630012081

Details

• 1 of 15 (6.67%) changed or added relevant lines in 2 files are covered.
• 10 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.1%) to 81.782%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/controllers/controllers.go	0	14	0.0%

Files with Coverage Reduction	New Missed Lines	%
pkg/test/expectations/expectations.go	2	93.37%
pkg/controllers/disruption/consolidation.go	4	88.14%
pkg/controllers/provisioning/scheduling/topologydomaingroup.go	4	86.21%

Totals
Change from base Build 16532859399:	-0.1%
Covered Lines:	10464
Relevant Lines:	12795

---

💛 - Coveralls

[tallaxes]

Would be good to list exactly what would be missing/disabled when this flag is used.

[tallaxes]

Are these status controllers only responsible for metrics? Anything else would be missing by disabling them? (For example, looks like they also issue transition events ...)

[DerekFrank]

They do also emit events for finalizers and status condition changes, but I think thats all they emit

[DerekFrank]

This option will disable all of the metrics that are just observing cluster state:

• karpenter_node_allocatable
• karpenter_node_total_pod_requests
• karpenter_node_total_pod_limits
• karpenter_node_total_daemon_requests
• karpenter_node_total_daemon_limits
• karpenter_node_system_overhead
• karpenter_node_current_lifetime_seconds
• karpenter_nodepool_limit
• karpenter_nodepool_usage
• karpenter_pod_state
• karpenter_pod_startup_duration_seconds
• karpenter_pod_unstarted_time_seconds
• karpenter_pod_bound_duration_seconds
• karpenter_pod_unbound_time_seconds
• karpenter_pod_provisioning_bound_duration_seconds
• karpenter_pod_provisioning_unbound_time_seconds
• karpenter_pod_provisioning_startup_duration_seconds
• karpenter_pod_provisioning_unstarted_time_seconds
• karpenter_pod_provisioning_scheduling_undecided_time_seconds
• operator_nodeclaim_status_condition_transition_seconds
• operator_nodeclaim_status_condition_count
• operator_nodeclaim_status_condition_current_status_seconds
• operator_nodeclaim_status_condition_transitions_total
• operator_nodepool_status_condition_transition_seconds
• operator_nodepool_status_condition_count
• operator_nodepool_status_condition_current_status_seconds
• operator_nodepool_status_condition_transitions_total
• operator_nodeclass_status_condition_transition_seconds
• operator_nodeclass_status_condition_count
• operator_nodeclass_status_condition_current_status_seconds
• operator_nodeclass_status_condition_transitions_total

[jmdeal]

We should figure out a more descriptive name than SimplifiedMetrics. Minimally, I think it should be clear from the name of the flag which metrics we're disabling. I'm thinking we could have something along the lines of DisableClusterStateMetrics and DisableStatusConditionMetrics.