Node Allocatable
Capacity:
cpu: 4
ephemeral-storage: 50824704Ki
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 8123340Ki
pods: 110
Allocatable:
cpu: 4
ephemeral-storage: 49442272013
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 8123340Ki
pods: 110
- Kubelet Node Allocatable 用来为 Kube 组件和 System 进程预留资源，从而保证当节点出现满负荷时也能保证 Kube 和 System 进程有足够的资源。
- 目前支持 cpu, memory,
ephemeral-storage三种资源预留。 - Node Capacity 是节点的所有硬件资源，
kube-reserved是给 kube 组件预留的资源，system-reserved是给系统进程预留的资源，eviction-threshold是 kubelet 驱逐的阈值设定，allocatable 才是真正调度器调度 Pod 时的参考值（保证节点上所有 Pods 的 request 资源不超过 Allocatable）。
Node Allocatable Resource = Node Capacity - Kube-reserved - system-reserved - eviction-threshold使用 CLI参数
--enforce-node-allocatable=pods
--kube-reserved=memory=...
--system-reserved=memory=...
--eviction-hard=...使用配置文件
/var/lib/kubelet/config.yaml
apiVersion: kubelet.config.k8s.io/v1beta1
......
enforceNodeAllocatable:
- pods
kubeReserved: # 配置 kube 资源预留
cpu: 500m
memory: 1Gi
ephemeral-storage: 1Gi
systemReserved: # 配置系统资源预留
memory: 1Gi
evictionHard: # 配置硬驱逐阈值
memory.available: "300Mi"
nodefs.available: "10%"rke1的情况
nodes:
- address: 10.10.10.1
user: rke
role: [controlplane,etcd]
- address: 10.10.10.2
user: rke
role: [controlplane,etcd,worker]
- address: 10.10.10.3
user: rke
role: [worker]
system_images:
kubernetes: rancher/hyperkube:v1.13.5-rancher1
services:
etcd:
backup_config:
enabled: true
interval_hours: 6
retention: 12
extra_args:
quota-backend-bytes: '4294967296'
kubelet:
cluster_domain: cluster.local
cluster_dns_server: 10.43.0.10
fail_swap_on: true
extra_args:
max-pods: 20
enforce-node-allocatable: 'pods'
system-reserved: 'cpu=1,memory=2000Mi'
kube-reserved: 'cpu=1.5,memory=3000Mi'
kube-controller:
cluster_cidr: 10.42.0.0/16
service_cluster_ip_range: 10.43.0.0/16
extra_args:
node-cidr-mask-size: '24'
node-monitor-period: '5s'
node-monitor-grace-period: '10s'
node-startup-grace-period: '20s'
pod-eviction-timeout: '10s'
kube-api:
service_cluster_ip_range: 10.43.0.0/16
service_node_port_range: 30000-32767
pod_security_policy: false
always_pull_images: false
dns:
provider: coredns
rke2的情况
microk8s的情况
它的kubelet 启动程序是
/snap/microk8s/2407/kubelite它的参数文件
/var/snap/microk8s/2407/args/kubelet
修改/var/snap/microk8s/2407/args/kubelet,追加以下内容
--enforce-node-allocatable=pods
--kube-reserved=cpu=500m
--kube-reserved=memory=1Gi
--system-reserved=cpu=500m
--system-reserved=memory=1Gi
--eviction-hard=10%