Graduate PrioritySortingWithinCohort feature gate to GA

[kannon92]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

Graduates the PrioritySortingWithinCohort feature gate to GA in version 0.17, with LockToDefault: true.

This feature has been enabled by default since v0.6 (Beta). Priority sorting within cohorts is now permanently enabled and can no longer be disabled.

Changes:

• Set the feature gate to GA with LockToDefault: true (to be removed in 0.19)
• Removed conditional code paths guarded by the feature gate in scheduler.go, fair_sharing_iterator.go, and workload.go
• Removed the dead code block in GetQueueOrderTimestamp that handled the disabled case with special preemption timestamp logic
• Removed integration test context "When borrowWithinCohort is used and PrioritySortingWithinCohort disabled"
• Removed unit test cases in TestEntryOrdering where prioritySorting: false
• Updated English and Chinese documentation to remove references to disabling the feature
• Updated versioned_feature_list.yaml in both site and test reference

Which issue(s) this PR fixes:

Part of #8855

Special notes for your reviewer:

The feature has been Beta and enabled by default since v0.6, so this graduation follows the standard lifecycle. The features import was removed from fair_sharing_iterator.go as it was the only usage in that file.

Does this PR introduce a user-facing change?

Graduate the PrioritySortingWithinCohort feature gate to GA. Priority sorting within cohorts is now always enabled and the feature gate is locked to true.

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[mbobrovskyi]

/lgtm

Thank you!

[k8s-ci-robot]

LGTM label has been added.

Details

Git tree hash: 3aa4431baddb40424fdc55650d9098b7111867b1

[tenzen-y]

I can approve this GA graduation, but I think that we should recommend enabling FS (for preemption enabling users) or AFS (for preemption disabling users) in the release note.

cc @mimowo @gabesaba

---

As far as I can remember, this FG, we introduced this mechanism with FG since we want to rapidly ship this one.
#1283

Additionally, we discussed adding this setting to the Kueue Configuration rather than using FG gating because this enhancement allows evil users to prioritize their workloads within Cohort.

After some discussions, we introduced FS and AFS to mitigate such evil user behavior.

[mimowo]

I can approve this GA graduation, but I think that we should recommend enabling FS (for preemption enabling users) or AFS (for preemption disabling users) in the release note.

+1 it will be better to say that users who disable PrioritySortingWithinCohort should transition to FairSharing or Admission Fair Sharing.

IIRC @amy used to use that, but AFAIK no longer uses it.

Additionally, we discussed adding this setting to the Kueue Configuration rather than using FG gating because this enhancement allows evil users to prioritize their workloads within Cohort.
After some discussions, we introduced FS and AFS to mitigate such evil user behavior.

Yes, but given we have FS I don't see a need to maintain this FG.

[tenzen-y]

IIRC @amy used to use that, but AFAIK no longer uses it.

Additionally, we discussed adding this setting to the Kueue Configuration rather than using FG gating because this enhancement allows evil users to prioritize their workloads within Cohort.
After some discussions, we introduced FS and AFS to mitigate such evil user behavior.

Yes, but given we have FS I don't see a need to maintain this FG.

Yes, I agree with you. For now, we can just recommend FS / AFS. If we can get strong motivation for the disabling of that, we can revisit the dedicated knob.

[kannon92]

What change should I make @mimowo and @tenzen-y?

[mimowo]

What change should I make @mimowo and @tenzen-y?

No change needed. Let's wait a week or so with the PR in case some community members have objections. In particular, I would like to hear from @amy to confirm she successfully managed to stop using the FG.

If no objections raised we can move the PR forward.

[mimowo]

/lgtm
/approve
For lazy consensus by the end of Feb. cc @tenzen-y
/hold

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kannon92, mimowo

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Details

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• OWNERS [mimowo]

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[tenzen-y]

/lgtm /approve For lazy consensus by the end of Feb. cc @tenzen-y /hold

I agree with you. Let's bring this topic to the next wg-batch meeting.

[tenzen-y]

/lgtm /approve For lazy consensus by the end of Feb. cc @tenzen-y /hold

I agree with you. Let's bring this topic to the next wg-batch meeting.

I added it to agenda.

[Michal Wozniak & Yuki Iwai] Kueue PrioritySortingWithinCohort GA graduation
#9259
https://docs.google.com/document/d/1XOeUN-K0aKmJJNq7H07r74n-mGgSFyiEDQ3ecwsGhec/edit?usp=sharing