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.
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.
the caching layer on endpoint is redundant.
Here are the 3 related objects in picture:
devicemanager <-> endpoint <-> plugin
Plugin is the source of truth for devices
and device health status.
devicemanager maintain healthyDevices,
unhealthyDevices, allocatedDevices based on updates
from plugin.
So there is no point for endpoint caching devices,
this patch is removing this caching layer on endpoint,
Also removing the Manager.Devices() since i didn't
find any caller of this other than test, i am adding a
notification channel to facilitate testing,
If we need to get all devices from manager in future,
it just need to return healthyDevices + unhealthyDevices,
we don't have to call endpoint after all.
This patch makes code more readable, data model been simplified.
