We will have two layers of the validation.
- the first part of the validation logic will be implemented under the
`ValidateKubeletConfiguration` method
- the second one that requires knowledge about machine topology and
node allocatable resources will be implemented under the memory manager.
Signed-off-by: Artyom Lukianov <alukiano@redhat.com>
Implements KEP 2000, Graceful Node Shutdown:
https://github.com/kubernetes/enhancements/tree/master/keps/sig-node/2000-graceful-node-shutdown
* Add new FeatureGate `GracefulNodeShutdown` to control
enabling/disabling the feature
* Add two new KubeletConfiguration options
* `ShutdownGracePeriod` and `ShutdownGracePeriodCriticalPods`
* Add new package, `nodeshutdown` that implements the Node shutdown
manager
* The node shutdown manager uses the systemd inhibit package, to
create an system inhibitor, monitor for node shutdown events, and
gracefully terminate pods upon a node shutdown.
Nit: remove capitalization of preferred
Remove line from kubelet and add to separate PR for easier merge
nit: dependency added to separate PR
Add check to ensure strict policy cannot be set without feature gate enabled
Topology Manager runs "none" policy by default.
Added constants for policies and updated documentation.
