When adding the ephemeral volume feature, the special case for
PersistentVolumeClaim volume sources in kubelet's host path and node
limits checks was overlooked. An ephemeral volume source is another
way of referencing a claim and has to be treated the same way.
The GetAllocatableDevices, needed to support the podresources
API, doesn't take into account the device health when computing
its output.
In this PR we address this gap and add unit tests along the way
to prevent regressions. This gives us a good initial coverage,
E2E tests to cover this case are much harder to write, because
we would need to inject faults to trigger the unhealthy status.
We will evaluate if adding these tests into later PRs.
Signed-off-by: Francesco Romani <fromani@redhat.com>
Remove the VolumeSubpath feature gate.
Feature gate convention has been updated since this was introduced to
indicate that they "are intended to be deprecated and removed after a
feature becomes GA or is dropped.".
If a pod is killed (no longer wanted) and then a subsequent create/
add/update event is seen in the pod worker, assume that a pod UID
was reused (as it could be in static pods) and have the next
SyncKnownPods after the pod terminates remove the worker history so
that the config loop can restart the static pod, as well as return
to the caller the fact that this termination was not final.
The housekeeping loop then reconciles the desired state of the Kubelet
(pods in pod manager that are not in a terminal state, i.e. admitted
pods) with the pod worker by resubmitting those pods. This adds a
small amount of latency (2s) when a pod UID is reused and the pod
is terminated and restarted.
A pod that has been rejected by admission will have status manager
set the phase to Failed locally, which make take some time to
propagate to the apiserver. The rejected pod will be included in
admission until the apiserver propagates the change back, which
was an unintended regression when checking pod worker state as
authoritative.
A pod that is terminal in the API may still be consuming resources
on the system, so it should still be included in admission.
The configuration is deprecated and targets removal for v1.23. Tests
cases have been changed as well.
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
Fixes two issues with how the pod worker refactor calculated the
pods that admission could see (GetActivePods() and
filterOutTerminatedPods())
First, completed pods must be filtered from the "desired" state
for admission, which arguably should be happening earlier in
config. Exclude the two terminal pods states from GetActivePods()
Second, the previous check introduced with the pod worker lifecycle
ownership changes was subtly wrong for the admission use case.
Admission has to include pods that haven't yet hit the pod worker,
which CouldHaveRunningContainers was filtering out (because the
pod worker hasn't seen them). Introduce a weaker check -
IsPodKnownTerminated() - that returns true only if the pod is in
a known terminated state (no running containers AND known to pod
worker). This weaker check may only be called from components that
need admitted pods, not other kubelet subsystems.
This commit does not fix the long standing bug that force deleted
pods are omitted from admission checks, which must be fixed by
having GetActivePods() also include pods "still terminating".
This is a knob added by runc 1.0.2 specifically for kubernetes,
which tells runc/libcontainer/cgroups/systemd v1 manager to not
freeze the cgroup in Set().
We set this knob here because this code is only used for pods
(rather than containers) management, and in this place we create or
update the pod cgroup with no device limits set, so we can skip the
freeze.
If this knob is not set, libcontainer's cgroup v1 manager tries to
figure out whether the freeze is needed or not, but it's a somewhat
expensive check to perform, thus the knob is a shortcut.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
