Kubernetes - Scheduler Plugins

Introduction

• Kubernetes scheduler uses a set of plugins to determine the scheduling of pods.
• Below are few examples:

1. PrioritySort
   • This plugin provides the logic to sort Pods in the scheduling queue based on their priority.
2. NodeResourcesFit
   • This plugin checks if a node has enough resources to meet the resource requirements of the Pod.
3. PodTopologySpread
   • This plugin helps to spread Pods evenly across different topology domains, such as regions, zones, nodes, and other user-defined topology domains.
4. InterPodAffinity
   • This plugin implements rules that govern whether or not Pods should be placed in the same topological domain as other Pods they’re related to based on labels.
5. NodeUnschedulable
   • This plugin filters out nodes that have their .spec.unschedulable field set to true.
6. TaintToleration
   • This plugin ensures that there is a match between the taints on a node and the tolerations declared by a Pod.
7. NodeAffinity
   • This plugin filters nodes based on the node affinity scheduling preferences declared by Pods.
8. VolumeBinding
   • This plugin checks if a node has the necessary volumes that a Pod requests, and can bind them if necessary.
9. DefaultPreemption
   • This plugin selects a node where a Pod can run and preempts other Pods on the node if necessary.
10. NodeResourcesBalancedAllocation
    • This plugin favors nodes that would obtain a more balanced resource usage if the Pod is scheduled there.
11. NodeResourcesLeastAllocated
    • This plugin favors nodes with fewer allocated resources, promoting better resource utilization and spreading the load more evenly.
12. DefaultBinder
    • This plugin binds a Pod to a Node. It is the final step in the scheduling process.