Optimize monitoring performance

[coldzerofear]

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What this PR does / why we need it:

Which issue(s) this PR fixes:
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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 60 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
pkg/lister/pod.go	0.00%	32 Missing ⚠️
pkg/monitor/nvidia/cudevshr.go	0.00%	28 Missing ⚠️

Flag	Coverage Δ
unittests	27.19% <0.00%> (-0.32%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
pkg/monitor/nvidia/cudevshr.go	0.00% <0.00%> (ø)
pkg/lister/pod.go	0.00% <0.00%> (ø)

... and 2 files with indirect coverage changes