optimize gc_controller.gcTerminated

[m3ngyang]

What type of PR is this?
/kind bug
/kind cleanup

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:
optimize some codes in gc_controller.gcTerminated:

1. don't do unnecessary sort if terminated pods number is under threshold.
2. when calling gcTerminated, gcc.terminatedPodThreshold must be > 0,

kubernetes/pkg/controller/podgc/gc_controller.go

Lines 93 to 95 in 84fe3db

	if gcc.terminatedPodThreshold > 0 {
	gcc.gcTerminated(pods)
	}

so, the following if won't work

kubernetes/pkg/controller/podgc/gc_controller.go

Lines 118 to 122 in 84fe3db

	deleteCount := terminatedPodCount - gcc.terminatedPodThreshold
	if deleteCount > terminatedPodCount {
	deleteCount = terminatedPodCount
	}

Does this PR introduce a user-facing change?:

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

NONE

[k8s-ci-robot]

Hi @m3ngyang. Thanks for your PR.

I'm waiting for a kubernetes 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.

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[m3ngyang]

/assign @foxish

[m3ngyang]

/assing @fedebongio
PTAL~

[m3ngyang]

/assign @liggitt
PTAL

[liggitt]

drop this, logging on no-op will spam the logs

[m3ngyang]

I re-pushed the commit and fixed the mentioned problems. @liggitt

[liggitt]

/ok-to-test
/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: liggitt, m3ngyang

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• pkg/controller/podgc/OWNERS [liggitt]

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[m3ngyang]

/test pull-kubernetes-integration