Kubernetes scheduling mechanism¶

The Kubernetes scheduling mechanism is the process by which the platform assigns pending [[Pods]] to suitable [[Nodes]]. It operates as the core decision-making engine that ensures workloads are distributed effectively across the cluster, governed by a resource model and specific default strategies.^[400-devops__06-Kubernetes__k8s-paas__原理及源码解析__README.md]

Core Components¶

Resource Model and Management¶

The foundation of scheduling lies in how Kubernetes views and manages cluster resources.^[400-devops__06-Kubernetes__k8s-paas__原理及源码解析__README.md] The system defines a specific resource model to track the availability and allocation of compute resources like CPU and memory.^[400-devops__06-Kubernetes__k8s-paas__原理及源码解析__README.md] This model allows the scheduler to make informed decisions regarding where to place new workloads based on the remaining capacity of each node.

Default Scheduling Strategy¶

Kubernetes employs a default scheduling strategy that serves as the primary logic for binding Pods to Nodes.^[400-devops__06-Kubernetes__k8s-paas__原理及源码解析__README.md] This strategy typically involves a multi-step process where the scheduler filters nodes that meet the Pod's requirements and then ranks the remaining nodes to select the most optimal fit.

Advanced Features¶

Priorities and Mandatory Mechanisms¶

To handle complex scenarios and ensure critical applications run, the scheduler includes features for priorities and mandatory mechanisms.^[400-devops__06-Kubernetes__k8s-paas__原理及源码解析__README.md] These mechanisms allow certain Pods to claim resources preferentially or enforce strict placement rules that cannot be violated, ensuring that high-priority workloads are not starved of resources.

Sources¶

• 400-devops__06-Kubernetes__k8s-paas__原理及源码解析__README.md