Align the behavior of HTTP-based lifecycle handlers and HTTP-based
probers, converging on the probers implementation. This fixes multiple
deficiencies in the current implementation of lifecycle handlers
surrounding what functionality is available.
The functionality is gated by the features.ConsistentHTTPGetHandlers feature gate.
Prevent Kubelet from incorrectly interpreting "not yet started" pods as "ready to terminate pods" by unifying responsibility for pod lifecycle into pod worker
A number of race conditions exist when pods are terminated early in
their lifecycle because components in the kubelet need to know "no
running containers" or "containers can't be started from now on" but
were relying on outdated state.
Only the pod worker knows whether containers are being started for
a given pod, which is required to know when a pod is "terminated"
(no running containers, none coming). Move that responsibility and
podKiller function into the pod workers, and have everything that
was killing the pod go into the UpdatePod loop. Split syncPod into
three phases - setup, terminate containers, and cleanup pod - and
have transitions between those methods be visible to other
components. After this change, to kill a pod you tell the pod worker
to UpdatePod({UpdateType: SyncPodKill, Pod: pod}).
Several places in the kubelet were incorrect about whether they
were handling terminating (should stop running, might have
containers) or terminated (no running containers) pods. The pod worker
exposes methods that allow other loops to know when to set up or tear
down resources based on the state of the pod - these methods remove
the possibility of race conditions by ensuring a single component is
responsible for knowing each pod's allowed state and other components
simply delegate to checking whether they are in the window by UID.
Removing containers now no longer blocks final pod deletion in the
API server and are handled as background cleanup. Node shutdown
no longer marks pods as failed as they can be restarted in the
next step.
See https://docs.google.com/document/d/1Pic5TPntdJnYfIpBeZndDelM-AbS4FN9H2GTLFhoJ04/edit# for details
We've changed the Ephemeral Containers API, and container type will no
longer be required. Since this is the only feature using it, remove it.
This reverts commit ba6f31a6c6.
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Remove rescheduler and corresponding tests from master
**What this PR does / why we need it**:
This is to remove rescheduler from master branch as we are promoting priority and preemption to beta.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Part of #57471
**Special notes for your reviewer**:
/cc @bsalamat @aveshagarwal
**Release note**:
```release-note
Remove rescheduler from master.
```
