Crane-scheduler
Crane-scheduler 介绍
Crane-scheduler 是一组基于scheduler framework的调度插件, 包含:
开始
安装 Prometheus
确保你的 Kubernetes 集群已安装 Prometheus。如果没有,请参考Install Prometheus.
配置 Prometheus 规则
配置 Prometheus 的规则以获取预期的聚合数据:
apiVersion: monitoring.coreos.com/v1
kind: PrometheusRule
metadata:
name: example-record
spec:
groups:
- name: cpu_mem_usage_active
interval: 30s
rules:
- record: cpu_usage_active
expr: 100 - (avg by (instance) (irate(node_cpu_seconds_total{mode="idle"}[30s])) * 100)
- record: mem_usage_active
expr: 100*(1-node_memory_MemAvailable_bytes/node_memory_MemTotal_bytes)
- name: cpu-usage-5m
interval: 5m
rules:
- record: cpu_usage_max_avg_1h
expr: max_over_time(cpu_usage_avg_5m[1h])
- record: cpu_usage_max_avg_1d
expr: max_over_time(cpu_usage_avg_5m[1d])
- name: cpu-usage-1m
interval: 1m
rules:
- record: cpu_usage_avg_5m
expr: avg_over_time(cpu_usage_active[5m])
- name: mem-usage-5m
interval: 5m
rules:
- record: mem_usage_max_avg_1h
expr: max_over_time(mem_usage_avg_5m[1h])
- record: mem_usage_max_avg_1d
expr: max_over_time(mem_usage_avg_5m[1d])
- name: mem-usage-1m
interval: 1m
rules:
- record: mem_usage_avg_5m
expr: avg_over_time(mem_usage_active[5m])
!!! warning “️Troubleshooting”
Prometheus 的采样间隔必须小于30秒,不然可能会导致规则无法正常生效。如:`cpu_usage_active`。
安装 Crane-scheduler
有两种选择:
- 安装 Crane-scheduler 作为第二个调度器
- 用 Crane-scheduler 替换原生 Kube-scheduler
安装 Crane-scheduler 作为第二个调度器
\=== “Main”
```bash
helm repo add crane https://gocrane.github.io/helm-charts
helm install scheduler -n crane-system --create-namespace --set global.prometheusAddr="REPLACE_ME_WITH_PROMETHEUS_ADDR" crane/scheduler
\=== “Mirror”
helm repo add crane https://finops-helm.pkg.coding.net/gocrane/gocrane
helm install scheduler -n crane-system --create-namespace --set global.prometheusAddr="REPLACE_ME_WITH_PROMETHEUS_ADDR" crane/scheduler
#### 用 Crane-scheduler 替换原生 Kube-scheduler
1. 备份`/etc/kubernetes/manifests/kube-scheduler.yaml`
cp /etc/kubernetes/manifests/kube-scheduler.yaml /etc/kubernetes/
2. 通过修改 kube-scheduler 的配置文件(`scheduler-config.yaml` ) 启用动态调度插件并配置插件参数:
apiVersion: kubescheduler.config.k8s.io/v1beta2 kind: KubeSchedulerConfiguration … profiles:
- schedulerName: default-scheduler
plugins:
filter:
enabled:
- name: Dynamic score: enabled:
- name: Dynamic
weight: 3
pluginConfig:
- name: Dynamic args: policyConfigPath: /etc/kubernetes/policy.yaml … ```
- 新建
/etc/kubernetes/policy.yaml
,用作动态插件的调度策略:
apiVersion: scheduler.policy.crane.io/v1alpha1
kind: DynamicSchedulerPolicy
spec:
syncPolicy:
##cpu usage
- name: cpu_usage_avg_5m
period: 3m
- name: cpu_usage_max_avg_1h
period: 15m
- name: cpu_usage_max_avg_1d
period: 3h
##memory usage
- name: mem_usage_avg_5m
period: 3m
- name: mem_usage_max_avg_1h
period: 15m
- name: mem_usage_max_avg_1d
period: 3h
predicate:
##cpu usage
- name: cpu_usage_avg_5m
maxLimitPecent: 0.65
- name: cpu_usage_max_avg_1h
maxLimitPecent: 0.75
##memory usage
- name: mem_usage_avg_5m
maxLimitPecent: 0.65
- name: mem_usage_max_avg_1h
maxLimitPecent: 0.75
priority:
##cpu usage
- name: cpu_usage_avg_5m
weight: 0.2
- name: cpu_usage_max_avg_1h
weight: 0.3
- name: cpu_usage_max_avg_1d
weight: 0.5
##memory usage
- name: mem_usage_avg_5m
weight: 0.2
- name: mem_usage_max_avg_1h
weight: 0.3
- name: mem_usage_max_avg_1d
weight: 0.5
hotValue:
- timeRange: 5m
count: 5
- timeRange: 1m
count: 2
- 修改
kube-scheduler.yaml
并用 Crane-scheduler的镜像替换 kube-scheduler 镜像:
...
image: docker.io/gocrane/crane-scheduler:0.0.23
...
安装crane-scheduler-controller: === “Main”
kubectl apply -f https://raw.githubusercontent.com/gocrane/crane-scheduler/main/deploy/controller/rbac.yaml
kubectl apply -f https://raw.githubusercontent.com/gocrane/crane-scheduler/main/deploy/controller/deployment.yaml
\=== “Mirror”
```bash
kubectl apply -f https://gitee.com/finops/crane-scheduler/raw/main/deploy/controller/rbac.yaml
kubectl apply -f https://gitee.com/finops/crane-scheduler/raw/main/deploy/controller/deployment.yaml
### 使用 Crane-scheduler 调度 Pod
使用以下示例测试 Crane-scheduler :
apiVersion: apps/v1 kind: Deployment metadata: name: cpu-stress spec: selector: matchLabels: app: cpu-stress replicas: 1 template: metadata: labels: app: cpu-stress spec: schedulerName: crane-scheduler hostNetwork: true tolerations:
- key: node.kubernetes.io/network-unavailable
operator: Exists
effect: NoSchedule
containers:
- name: stress
image: docker.io/gocrane/stress:latest
command: ["stress", "-c", "1"]
resources:
requests:
memory: "1Gi"
cpu: "1"
limits:
memory: "1Gi"
cpu: "1"
!!! Note
如果想将crane-scheduler
用作默认调度器,请将crane-scheduler
更改为default-scheduler
。
如果测试 pod 调度成功,将会有以下事件:
Type Reason Age From Message
Normal Scheduled 28s crane-scheduler Successfully assigned default/cpu-stress-7669499b57-zmrgb to vm-162-247-ubuntu ```