diff --git a/content/en/docs/concepts/scheduling-eviction/scheduling-framework.md b/content/en/docs/concepts/scheduling-eviction/scheduling-framework.md index d09934aa7d..ea0d981055 100644 --- a/content/en/docs/concepts/scheduling-eviction/scheduling-framework.md +++ b/content/en/docs/concepts/scheduling-eviction/scheduling-framework.md @@ -52,7 +52,18 @@ equivalent to "Predicate" and "Scoring" is equivalent to "Priority function". One plugin may register at multiple extension points to perform more complex or stateful tasks. -{{< figure src="/images/docs/scheduling-framework-extensions.png" title="scheduling framework extension points" class="diagram-large">}} +{{< figure src="/images/docs/scheduling-framework-extensions.png" title="Scheduling framework extension points" class="diagram-large">}} + +### PreEnqueue {#pre-enqueue} + +These plugins are called prior to adding Pods to the internal active queue, where Pods are marked as +ready for scheduling. + +Only when all PreEnqueue plugins return `Success`, the Pod is allowed to enter the active queue. +Otherwise, it's placed in the internal unschedulable Pods list, and doesn't get an `Unschedulable` condition. + +For more details about how internal scheduler queues work, read +[Scheduling queue in kube-scheduler](https://github.com/kubernetes/community/blob/f03b6d5692bd979f07dd472e7b6836b2dad0fd9b/contributors/devel/sig-scheduling/scheduler_queues.md). ### QueueSort {#queue-sort} diff --git a/static/images/docs/scheduling-framework-extensions.png b/static/images/docs/scheduling-framework-extensions.png index d27f89abc4..43fe0f233e 100644 Binary files a/static/images/docs/scheduling-framework-extensions.png and b/static/images/docs/scheduling-framework-extensions.png differ