* Start using FakeRuntime to replace FakeDockerClient in unit tests.
* Move and adapt docker-specific tests (e.g. creating/deleting infra
containers) to manager_test.go in dockertools.
- Delete nodes when they are no longer ready and don't exist in the
cloud provider.
- Label each node with it's hostname.
- Add flag to skip node registration.
- Add a test for registering an existing node.
We recently changed `SyncPods` to filter out terminated pods at the beginning
for two reasons:
* performance: kubelet no longer keeps goroutines to checks containers for
terminated pods.
* correctness: kubelet relies on inspecting dead containers to generate
pod status. Because dead containers may get garbage collected and
kubelet does not have checkpoints yet, syncing terminated pod could
lead to modifying the status of a terminated pod.
However, even though kubelet should not *sync* the terminated pods, it
should not attempt to remove the directories and volumes for such
pods as long as they have not been deleted. This change fixes aggresive
directory removal by passing all pods (including terminated pods) to the
cleanup functions.
Per-pod workers have sufficient knowledge to determine whether a pod has
exceeded the active deadline, and they set the status at the end of each sync.
Move the active deadline check to generatePodStatus so that per pod workers
can update the pod status directly. This eliminates the possibility of a race
condition where both SyncPods and the pod worker are updating the status, which
could lead to temporary erratic pod status behavior (pod phase: failed ->
running -> failed).
Pod statuses are periodically writtien to the status manager, and status
manager sets the start time of the pod. All non-status-modifying code should
perform cache lookup and should not attempt to generate pod status on its own.
Kubelet will stop accepting new pods if it detects low disk space on root fs or fs holding docker images.
Running pods are not affected. low-diskspace-threshold-mb is used to configure the low diskspace threshold.
This change instructs kubelet to switch to using the Runtime interface. In order
to do it, the change moves the Prober instantiation to DockerManager.
Note that most of the tests in kubelet_test.go needs to be migrated to
dockertools. For now, we use type assertion to convert the Runtime interface to
DockerManager in most tests.
This change removes docker-specifc code in killUnwantedPods. It
also instructs the cleanup code to move away from interacting with
containers directly. They should always deal with the pod-level
abstraction if at all possible.