Automatic merge from submit-queue
Improved code coverage for pkg/kubelet/util.
The test coverage for pkg/kubelet/util.go increased from 45.1%
to 84.3%.
**What this PR does / why we need it**:
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
```
Automatic merge from submit-queue (batch tested with PRs 45685, 45572, 45624, 45723, 45733)
Remove unused fields from Kubelet struct
Just a small attempt to clean up some unused fields in the kubelet struct. This doesn't make any actual code changes.
/assign @mtaufen
Automatic merge from submit-queue (batch tested with PRs 41994, 41969, 41997, 40952, 40576)
Guaranteed admission for Critical Pods
This is the first step in implementing node-level preemption for critical pods.
It defines the AdmissionFailureHandler interface, which allows callers, like the kubelet, to define how failed predicates are handled, and take steps to correct failures if necessary.
In the kubelet's implementation, it triggers preemption if the pod being admitted is critical, and if the only failed predicates are InsufficientResourceErrors, then it prempts (not yet implemented) other other pods to allow admission of the critical pod.
cc: @vishh
Automatic merge from submit-queue (batch tested with PRs 41714, 41510, 42052, 41918, 31515)
Switch scheduler to use generated listers/informers
Where possible, switch the scheduler to use generated listers and
informers. There are still some places where it probably makes more
sense to use one-off reflectors/informers (listing/watching just a
single node, listing/watching scheduled & unscheduled pods using a field
selector).
I think this can wait until master is open for 1.7 pulls, given that we're close to the 1.6 freeze.
After this and #41482 go in, the only code left that references legacylisters will be federation, and 1 bit in a stateful set unit test (which I'll clean up in a follow-up).
@resouer I imagine this will conflict with your equivalence class work, so one of us will be doing some rebasing 😄
cc @wojtek-t @gmarek @timothysc @jayunit100 @smarterclayton @deads2k @liggitt @sttts @derekwaynecarr @kubernetes/sig-scheduling-pr-reviews @kubernetes/sig-scalability-pr-reviews
Where possible, switch the scheduler to use generated listers and
informers. There are still some places where it probably makes more
sense to use one-off reflectors/informers (listing/watching just a
single node, listing/watching scheduled & unscheduled pods using a field
selector).
Automatic merge from submit-queue
Optional configmaps and secrets
Allow configmaps and secrets for environment variables and volume sources to be optional
Implements approved proposal c9f881b7bb
Release note:
```release-note
Volumes and environment variables populated from ConfigMap and Secret objects can now tolerate the named source object or specific keys being missing, by adding `optional: true` to the volume or environment variable source specifications.
```
Automatic merge from submit-queue (batch tested with PRs 37228, 40146, 40075, 38789, 40189)
Cleanup temp dirs
So funny story my /tmp ran out of space running the unit tests so I am cleaning up all the temp dirs we create.
Klaus Ma