Kubernetes Pod QoS

The basic concept and use of QoS will not be repeated here

https://kubernetes.io/zh/docs/tasks/configure-pod-container/quality-service-pod/

This is mainly to explain a problem

QoS acts on the pod, but the resources that determine QoS act on the container. Then, when there is only one container on a pod, this problem becomes very simple

apiVersion: v1
kind: Pod
metadata:
  name: qos-demo
  namespace: lizhe
spec:
  containers:
  - name: qos-demo-ctr
    image: nginx
    resources:
      limits:
        memory: "200Mi"
        cpu: "700m"
      requests:
        memory: "200Mi"
        cpu: "700m"

apiVersion: v1
kind: Pod
metadata:
  name: qos-demo
  namespace: lizhe
spec:
  containers:
  - name: qos-demo-ctr1
    image: busybox
    command:
    - sleep
    - infinity
    resources:
      limits:
        memory: "200Mi"
        cpu: "700m"
      requests:
        memory: "200Mi"
        cpu: "700m"
  - name: qos-demo-ctr2
    image: busybox
    command:
    - sleep
    - infinity
    resources:
      limits:
        memory: "300Mi"
        cpu: "800m"
      requests:
        memory: "300Mi"
        cpu: "800m"

If the requests and limits of container2 are inconsistent, the QoS should be burstable for container2 and guaranteed for container1

container1

requests 200,700 limits 200,700

container2

requests 200,700 limits 300,800

apiVersion: v1
kind: Pod
metadata:
  name: qos-demo
  namespace: lizhe
spec:
  containers:
  - name: qos-demo-ctr1
    image: busybox
    command:
    - sleep
    - infinity
    resources:
      limits:
        memory: "200Mi"
        cpu: "700m"
      requests:
        memory: "200Mi"
        cpu: "700m"
  - name: qos-demo-ctr2
    image: busybox
    command:
    - sleep
    - infinity
    resources:
      limits:
        memory: "300Mi"
        cpu: "800m"
      requests:
        memory: "200Mi"
        cpu: "700m"

conclusion
QoS really works on pod
The QoS is determined by the resources of the container

All container requests and limits are consistent == guaranteed
There are inconsistencies == burstable
No configuration == best effort