The current behavior is to select only based on pod priority, where any
pod with higher priority can preempt any pod with lower priority.
In our case, we have multiple priority classes but where only a subset
of those are considered preemptible. Here's roughly how this looks:
- High priority: higher in the scheduling queue, not preemptible
- Low priority: lower in the scheduling queue, not preemptible
- Preemptible priority: lowest in the scheduling queue, preemptible
This PR allows the preemption selection to be configured against the
`DefaultPreemption` plugin, rather than needing to reimplement the
plugin itself. The structure used here mimics [what's currently being
done for the `Evaluator`](https://github.com/kubernetes/kubernetes/blob/release-1.32/pkg/scheduler/framework/preemption/preemption.go#L161-L165),
where a `PreemptPod` callback may be overridden to customize what
happens when performing a preemption.
This PR also updates the plugin's tests to call the updated `New()`
function rather than constructing `DefaultPreemption` directly, so
that `New()` is now being exercised in tests.
Informer callbacks must be prepared to get cache.DeletedFinalStateUnknown as
the deleted object. They can use that as hint that some information may have
been missed, but typically they just retrieve the stored object inside it.
This PR focus on utils in scheduler. When to patch pod status or delete pod,
it is better to use an inherited context.
Although this do not take a big effect in preventing goroutine leak, but it is a best practice
Signed-off-by: kerthcet <kerthcet@gmail.com>
- replace error with NodeToStatusMap in Preempt() signature
- eliminate podPreemptor interface and expose its functions statelessly
- move logic in scheduler.go#preempt to generic_scheduler.go#Preempt()
- move extender related API from pkg/scheduler/api to pkg/scheduler/apis/extender/v1
- alias extenderv1 to pkg/scheduler/apis/extender/v1
- use NodeScore and NodeScoreList in non-extender logic
- Remove string decode logic. It's not really helping to find the
conflict ports, and it's expensive to do encoding/decoding
- Not to parse the container ports information in predicate meta, use
straight []*v1.ContainerPort
- Use better data structure to search port conflict based on ip
addresses
- Collect scattered source code into common place
This moves plugin/pkg/scheduler to pkg/scheduler and
plugin/cmd/kube-scheduler to cmd/kube-scheduler.
Bulk of the work was done with gomvpkg, except for kube-scheduler main
package.
