From 3e639b3c8ee5e7ed383ec54a5f24743f92955c49 Mon Sep 17 00:00:00 2001 From: Alexander Zimmermann <7714821+alexzimmer96@users.noreply.github.com> Date: Thu, 6 Feb 2020 14:45:34 +0100 Subject: [PATCH] Added a note about built-in priority-classes (#18979) * Added a note about build-in priority-classes * Update content/en/docs/concepts/configuration/pod-priority-preemption.md Co-Authored-By: Tim Bannister Co-authored-by: Tim Bannister --- .../docs/concepts/configuration/pod-priority-preemption.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/content/en/docs/concepts/configuration/pod-priority-preemption.md b/content/en/docs/concepts/configuration/pod-priority-preemption.md index 4b490b827e..399f8b4e22 100644 --- a/content/en/docs/concepts/configuration/pod-priority-preemption.md +++ b/content/en/docs/concepts/configuration/pod-priority-preemption.md @@ -62,6 +62,12 @@ To use priority and preemption in Kubernetes 1.11 and later, follow these steps: Keep reading for more information about these steps. +{{< note >}} +Kubernetes already ships with two PriorityClasses: +`system-cluster-critical` and `system-node-critical`. +These are common classes and are used to [ensure that critical components are always scheduled first](/docs/tasks/administer-cluster/guaranteed-scheduling-critical-addon-pods/). +{{< /note >}} + If you try the feature and then decide to disable it, you must remove the PodPriority command-line flag or set it to `false`, and then restart the API server and scheduler. After the feature is disabled, the existing Pods keep