K8S 容器的資源需求、資源限制

容器的資源需求，資源限制

• requests:需求，最低保障；
• limits：限制，硬限制；

CPU：
1 顆邏輯 CPU
1=1000，millicores
500m=0.5CPU

QoS：

1. Guranteed : 每個容器 同時設置CPU和內存的requests和limits
   即 :cpU.limits=cpu.request, memory.limits=memory.requests
2. Burstable：至少有一個容器設置CPU或內存資源的requests屬性
3. BestEffort：沒有任何一個容器設置了requests或limits屬性

# 查看節點上的 taint
kubectl describe nodes node1 |grep -E '(Roles|Taints)'
kubectl describe nodes node2 |grep -E '(Roles|Taints)'

kubectl taint node node1 node-type-
kubectl taint node node2 node-type-

mkdir ~/metrics ; cd ~/metrics

vi pod-demo.yaml
apiVersion: v1
kind: Pod
metadata:
  name: pod-demo
  labels:
    app: myapp
    tier: frontend
spec:
  containers:
  - name: myapp
    image: ikubernetes/stress-ng
    command: ["/usr/bin/stress-ng", "-c 1", "--metrics-brief"]
    resources:
      requests:
        cpu: "200m"
        memory: "128Mi"
      limits:
        cpu: "500m"
        memory: "512Mi"

kubectl apply -f pod-demo.yaml 

kubectl exec pod-demo -- top

# 查看 Qos
kubectl describe pod pod-demo|grep "QoS Class"