- allocatePodResources logic altered to allow for container by container
device allocation.
- New type PodReusableDevices
- New field in devicemanager devicesToReuse
- Where previously we called manager.AddContainer(), we now call both
manager.Allocate() and manager.AddContainer().
- Some test cases now have two expected errors. One each
from Allocate() and AddContainer(). Existing outcomes are unchanged.
GetTopologyPodAdmitHandler() now returns a lifecycle.PodAdmitHandler
type instead of the TopologyManager directly. The handler it returns
is generally responsible for attempting to allocate any resources that
require a pod admission check. When the TopologyManager feature gate
is on, this comes directly from the TopologyManager. When it is off,
we simply attempt the allocations ourselves and fail the admission
on an unexpected error. The higher level kubelet.go feature gate
check will be removed in an upcoming PR.
This change will not work on its own. Higher level code needs to make
sure and call Allocate() before AddContainer is called. This is already
being done in cases when the TopologyManager feature gate is enabled (in
the PodAdmitHandler of the TopologyManager). However, we need to make
sure we add proper logic to call it in cases when the TopologyManager
feature gate is disabled.
This change will not work on its own. Higher level code needs to make
sure and call Allocate() before AddContainer is called. This is already
being done in cases when the TopologyManager feature gate is enabled (in
the PodAdmitHandler of the TopologyManager). However, we need to make
sure we add proper logic to call it in cases when the TopologyManager
feature gate is disabled.
Having this interface allows us to perform a tight loop of:
for each container {
containerHints = {}
for each provider {
containerHints[provider] = provider.GatherHints(container)
}
containerHints.MergeAndPublish()
for each provider {
provider.Allocate(container)
}
}
With this in place we can now be sure that the hints gathered in one
iteration of the loop always consider the allocations made in the
previous.
Instead of having a single call for Allocate(), we now split this into two
functions Allocate() and UpdatePluginResources().
The semantics split across them:
// Allocate configures and assigns devices to a pod. From the requested
// device resources, Allocate will communicate with the owning device
// plugin to allow setup procedures to take place, and for the device
// plugin to provide runtime settings to use the device (environment
// variables, mount points and device files).
Allocate(pod *v1.Pod) error
// UpdatePluginResources updates node resources based on devices already
// allocated to pods. The node object is provided for the device manager to
// update the node capacity to reflect the currently available devices.
UpdatePluginResources(
node *schedulernodeinfo.NodeInfo,
attrs *lifecycle.PodAdmitAttributes) error
As we move to a model in which the TopologyManager is able to ensure
aligned allocations from the CPUManager, devicemanger, and any
other TopologManager HintProviders in the same synchronous loop, we will
need to be able to call Allocate() independently from an
UpdatePluginResources(). This commit makes that possible.
If we don't install docker and install just containerd apt packages,
there is no docker group. In this scenario, we should not add the gid to
config.toml
