[Cherry-pick 1.13] Fix scheduler panic by moving InitKubeSchedulerRelatedMetrics outside…

[JesseStutler]

Cherry-picks #4731 for release-1.13.

What type of PR is this?

Bug fix

What this PR does / why we need it:

Scheduler panics with nil pointer dereference during pod scheduling when started without --enable-metrics=true. The Kubernetes scheduler framework plugins unconditionally access k8smetrics.Goroutines, which was only initialized when metrics were enabled.

Changes:

• Moved metrics.InitKubeSchedulerRelatedMetrics() outside the if opt.EnableMetrics || opt.EnablePprof block in cmd/scheduler/app/server.go
• Ensures k8smetrics.Goroutines is always initialized before scheduler starts

Which issue(s) this PR fixes:

Fixes #4729

Does this PR introduce a user-facing change?

Fix scheduler panic when starting without --enable-metrics=true flag

[volcano-sh-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[gemini-code-assist]

Summary of Changes

Hello @JesseStutler, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a critical bug where the Kubernetes scheduler would panic due to a nil pointer dereference if started with metrics disabled. The fix ensures that a crucial metrics initialization function, which is unconditionally accessed by scheduler framework plugins, is always called regardless of whether metrics or pprof are explicitly enabled, thereby stabilizing the scheduler's startup process.

Highlights

• Scheduler Metric Initialization: The metrics.InitKubeSchedulerRelatedMetrics() call has been moved outside the conditional block that checks for EnableMetrics or EnablePprof.
• Preventing Nil Pointer Dereference: This change ensures that k8smetrics.Goroutines is always initialized, preventing a nil pointer dereference panic when the scheduler starts without metrics enabled.

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[gemini-code-assist]

Code Review

This pull request addresses a critical bug that causes the scheduler to panic when started without metrics enabled. The fix involves moving the initialization of Kubernetes scheduler-related metrics to be unconditional, which correctly prevents the nil pointer dereference. The change is simple, effective, and includes a clear comment explaining why the initialization is always necessary. The fix is well-implemented and resolves the issue as described.

[hajnalmt]

/close

Merged with #4770

[volcano-sh-bot]

@hajnalmt: Closed this PR.

Details

In response to this:

/close

Merged with #4770

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