Automatic merge from submit-queue.
Update priority eviction docs
After discussion with @dchen1107 and @bsalamat I think it would be simpler to start with a tiered eviction sorting rather than by using a function. See https://github.com/kubernetes/community/pull/846#pullrequestreview-66920328 for some of the rationale.
This PR makes two changes:
1. Changes the release at which changes take effect to 1.9 (since implementation missed 1.8)
2. Changes the strategy from (usage > requests, func(priority, usage - requests)) to (usage > requests, priority, usage - requests)
cc @dchen1107 @derekwaynecarr @vishh
Kubernetes Submit Queue
David Ashpole
huzhengchuan
Lee Verberne
Slava Semushin
Garrett Rodrigues