Add pod priority and preemption

[bsalamat]

Feature Description

• One-line feature description (can be used as a release note): Pod priority and preemption enables Kubernetes scheduler to schedule more important Pods first and when cluster is out of resources, it removes less important pods to create room for more important ones. The importance is specified by priority.
• Primary contact (assignee): @bsalamat
• Responsible SIGs: scheduling
• Design proposal link (community repo): https://github.com/kubernetes/community/blob/master/contributors/design-proposals/scheduling/pod-preemption.md
• Link to e2e and/or unit tests: https://github.com/kubernetes/kubernetes/blob/master/test/integration/scheduler/preemption_test.go
• Reviewer(s) - (for LGTM) recommend having 2+ reviewers (at least one from code-area OWNERS file) agreed to review. Reviewers from multiple companies preferred: @k82cn @davidopp
• Approver (likely from SIG/area to which feature belongs): @k82cn
• Feature target (which target equals to which milestone):
  • Alpha release target (x.y) 1.8
  • Beta release target (x.y) 1.11
  • Stable release target (x.y) 1.14

/stage beta
/sig scheduling
/kind feature

[justaugustus]

/assign @bsalamat

[justaugustus]

@bsalamat --
We're doing one more sweep of the 1.11 Features tracking spreadsheet.
Would you mind filling in any incomplete / blank fields for this feature's line item?

[kacole2]

@bsalamat This feature was worked on in the previous milestone, so we'd like to check in and see if there are any plans for this to graduate stages in Kubernetes 1.12.

If there are any updates, please explicitly ping @justaugustus, @kacole2, @robertsandoval, @rajendar38 to note that it is ready to be included in the Features Tracking Spreadsheet for Kubernetes 1.12.

---

Please note that the Features Freeze is July 31st, after which any incomplete Feature issues will require an Exception request to be accepted into the milestone.

In addition, please be aware of the following relevant deadlines:

• Docs deadline (open placeholder PRs): 8/21
• Test case freeze: 8/28

Please make sure all PRs for features have relevant release notes included as well.

Happy shipping!

[bsalamat]

This feature is built and graduated to Beta in 1.11. We don't have a clear milestone for GA at this point as we have not received enough feedback about it yet.

[fejta-bot]

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