1. Core Kubelet changes to implement In-place Pod Vertical Scaling.
2. E2E tests for In-place Pod Vertical Scaling.
3. Refactor kubelet code and add missing tests (Derek's kubelet review)
4. Add a new hash over container fields without Resources field to allow feature gate toggling without restarting containers not using the feature.
5. Fix corner-case where resize A->B->A gets ignored
6. Add cgroup v2 support to pod resize E2E test.
KEP: /enhancements/keps/sig-node/1287-in-place-update-pod-resources
Co-authored-by: Chen Wang <Chen.Wang1@ibm.com>
cpu.cfs_period_us is measured in microseconds in the kernel but
provided in time.Duration by the user, that change clarifies the code
to make this evident to the reader.
Also, the minimum value for that feature is 1ms and not 1μs, and this
change alters the validation to reject values smaller than 1ms.
cpu.cfs_period_us is 100μs by default despite having an "ms" unit
for some unfortunate reason. Documentation:
https://www.kernel.org/doc/html/latest/scheduler/sched-bwc.html#management
The desired effect of that change is more clarity on the default value
so users would be aware that the 10ms custom value would be
not 0.1x of the default, but 100x of it.
On systems where the calculated cpu shares results in a value above the
max value in linux, containers getting that value are unable to start.
This occur on systems with 300+ cpu cores, and where containers are
given such a value.
This issue was fixed for the pod and qos control groups in the similar
cm.MilliCPUToShares that also has tests verifying the behavior. Since
this code already has an dependency on kubelet/cm, lets reuse that code
instead.
