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文章目录
- 前言
- 应用
- 环境
- 1.VPA应用案例 updateMode: "Off"
- （1）创建应用实例
- （2）创建vpa
- 2.VPA应用案例 updateMode: "Auto"
- （1）创建应用
- （2）创建vpa
- （3）执行压测
前言
有任何疑问或不懂的地方均可评论或私信，欢迎交流
关于VPA的详细解释
链接: VPA的详细解释
策略
在VPA中，updateMode 是一个重要的配置选项，它决定了VPA如何应用其提供的资源建议。根据不同的设置，VPA可以采取不同的策略来更新Pod的资源配置：
Off：
VPA不会应用任何资源推荐，只是收集和显示数据。
Auto
概述:
自动调整策略在无需重启 Pod 的情况下动态调整其资源请求。
特性:
动态调整： Pod 的资源请求在运行时逐步增加。
优点：
无需重启 Pod 即可调整资源，最小化中断。
提供更及时的资源调整，适合短周期和不稳定的负载。
缺点：
由于容器运行时资源的硬限制，可能无法完全满足新资源请求，导致资源不足。
Recreate
概述:
当资源需求变化时，使用重建策略重新启动 Pod 以调整资源请求。
特性:
重启调整：Pod 会被杀死并重新创建，以适应新的资源请求。
优点：
确保 Pod 能获取到新的资源请求，避免运行时的资源限制问题。
适合稳定负载且可以容忍短暂停机的应用。
缺点：
重启 Pod 会引起短暂的服务中断。
不适合要求高可用性且不能容忍重启的工作负载。
Initial
概述:
初始调整策略仅在 Pod 第一次创建时设置资源请求，不会对运行中的 Pod 进行调整。
特性:
静态调整：在 Pod 创建时基于历史数据设定初始资源请求。
优点：
避免了运行时调整带来的复杂性。
适合长期运行的负载，初始设置资源合理即可。
缺点：
无法调整已经运行的 Pod 的资源，若需求变化则需手动干预。
应用
环境
虚拟机
| Ip | 主机名 | cpu | 内存 | 硬盘 |
|---|---|---|---|---|
| 192.168.10.11 | master01 | 2cpu双核 | 4G | 100G |
| 192.168.10.12 | worker01 | 2cpu双核 | 4G | 100G |
| 192.168.10.13 | worker02 | 2cpu双核 | 4G | 100G |
版本 centos7.9
已部署k8s-1.27
1.VPA应用案例 updateMode: “Off”
（1）创建应用实例
VPA不会应用任何资源推荐，只是收集和显示数据。
vim 03-nginx.yaml
apiVersion: apps/v1
kind: Deployment
metadata:labels:app: nginxname: nginxnamespace: default
spec:replicas: 2selector:matchLabels:app: nginxtemplate:metadata:labels:app: nginxspec:containers:- name: nginximage: nginx:latest imagePullPolicy: IfNotPresentresources:requests:cpu: 100mmemory: 250Mi
---
apiVersion: v1
kind: Service
metadata:name: nginxnamespace: default
spec:type: NodePortports:- port: 80targetPort: 80selector:app: nginx
kubectl apply -f 03-nginx.yaml
kubectl get pods
kubectl get svc
（2）创建vpa
使用updateMode: "Off"模式，这种模式仅获取资源推荐，不更新Pod
vim nginx-vpa.yaml
apiVersion: autoscaling.k8s.io/v1
kind: VerticalPodAutoscaler
metadata:name: nginx-vpanamespace: default
spec:targetRef:apiVersion: "apps/v1"kind: Deploymentname: nginxupdatePolicy:updateMode: "Off"resourcePolicy:containerPolicies:- containerName: "nginx"minAllowed:cpu: "250m"memory: "100Mi"maxAllowed:cpu: "2000m"memory: "2048Mi"
kubectl apply -f nginx-vpa.yamlkubectl get vpa
稍等片刻
kubectl describe vpa nginx-vpa
Name: nginx-vpa
Namespace: default
Labels: <none>
Annotations: <none>
API Version: autoscaling.k8s.io/v1
Kind: VerticalPodAutoscaler
Metadata:Creation Timestamp: 2024-06-09T11:10:34ZGeneration: 1Resource Version: 19449UID: be19f937-fb0c-4c33-a559-4e5aa52043b8
Spec:Resource Policy:Container Policies:Container Name: nginxMax Allowed:Cpu: 2000mMemory: 2048MiMin Allowed:Cpu: 250mMemory: 100MiTarget Ref:API Version: apps/v1Kind: DeploymentName: nginxUpdate Policy:Update Mode: Off
Status:Conditions:Last Transition Time: 2024-06-09T11:11:17ZStatus: TrueType: RecommendationProvidedRecommendation:Container Recommendations:Container Name: nginxLower Bound:Cpu: 250mMemory: 262144kTarget:Cpu: 250mMemory: 262144kUncapped Target:Cpu: 25mMemory: 262144kUpper Bound:Cpu: 1142mMemory: 1194357142
Events: <none>
解释如下：
Recommendation:：包含对Pod资源需求的推荐值。
Container Recommendations:：针对特定容器的推荐值。
Container Name:：容器名称。
Lower Bound:：推荐的下限资源量。
Target:：推荐的最优资源量。
Uncapped Target:：如果没有上限约束，则为目标资源量。
Upper Bound:：推荐的上限资源量。
kubectl get svc
yum -y install httpd-tools
ab -c 1000 -n 100000000 http://192.168.10.11:30478/
打开一个新终端
kubectl describe vpa nginx-vpa
Name: nginx-vpa
Namespace: default
Labels: <none>
Annotations: <none>
API Version: autoscaling.k8s.io/v1
Kind: VerticalPodAutoscaler
Metadata:Creation Timestamp: 2024-06-09T11:10:34ZGeneration: 1Resource Version: 20221UID: be19f937-fb0c-4c33-a559-4e5aa52043b8
Spec:Resource Policy:Container Policies:Container Name: nginxMax Allowed:Cpu: 2000mMemory: 2048MiMin Allowed:Cpu: 250mMemory: 100MiTarget Ref:API Version: apps/v1Kind: DeploymentName: nginxUpdate Policy:Update Mode: Off
Status:Conditions:Last Transition Time: 2024-06-09T11:11:17ZStatus: TrueType: RecommendationProvidedRecommendation:Container Recommendations:Container Name: nginxLower Bound:Cpu: 250mMemory: 262144kTarget:Cpu: 250mMemory: 262144kUncapped Target:Cpu: 25mMemory: 262144kUpper Bound:Cpu: 802mMemory: 838810574
Events: <none>
由于使用updateMode: “Off”，所以没有更新pod
kubectl get pods
2.VPA应用案例 updateMode: “Auto”
此模式当目前运行的pod的资源达不到VPA的推荐值，就会执行pod驱逐，重新部署新的足够资源的服务
（1）创建应用
vim 05-nginx.yaml
apiVersion: apps/v1
kind: Deployment
metadata:labels:app: nginxname: nginxnamespace: default
spec:replicas: 2selector:matchLabels:app: nginxtemplate:metadata:labels:app: nginxspec:containers:- name: nginximage: nginx:latestimagePullPolicy: IfNotPresentresources:requests:cpu: 100mmemory: 50Mi
---
apiVersion: v1
kind: Service
metadata:name: nginxnamespace: default
spec:type: NodePortports:- port: 80targetPort: 80selector:app: nginx
kubectl apply -f 05-nginx.yamlkubectl get pods
kubectl apply -f 05-nginx.yamlkubectl get pods
（2）创建vpa
vim nginx-vpa-auto.yaml
apiVersion: autoscaling.k8s.io/v1
kind: VerticalPodAutoscaler
metadata:name: nginx-vpa-autonamespace: default
spec:targetRef:apiVersion: "apps/v1"kind: Deploymentname: nginxupdatePolicy:updateMode: "Auto"resourcePolicy:containerPolicies:- containerName: "nginx"minAllowed:cpu: "250m"memory: "100Mi"maxAllowed:cpu: "2000m"memory: "2048Mi"
kubectl apply -f nginx-vpa-auto.yaml
kubectl get vpa
（3）执行压测
kubectl get svc
ab -c 1000 -n 1000000000 http://192.168.10.11:31115/
打开另一个终端
kubectl describe vpa nginx-vpa-auto
Name: nginx-vpa-auto
Namespace: default
Labels: <none>
Annotations: <none>
API Version: autoscaling.k8s.io/v1
Kind: VerticalPodAutoscaler
Metadata:Creation Timestamp: 2024-06-09T11:27:07ZGeneration: 1Resource Version: 21845UID: 453b03aa-fba5-4bcd-aa66-f85e43a57521
Spec:Resource Policy:Container Policies:Container Name: nginxMax Allowed:Cpu: 2000mMemory: 2048MiMin Allowed:Cpu: 250mMemory: 100MiTarget Ref:API Version: apps/v1Kind: DeploymentName: nginxUpdate Policy:Update Mode: Auto
Status:Conditions:Last Transition Time: 2024-06-09T11:27:17ZStatus: TrueType: RecommendationProvidedRecommendation:Container Recommendations:Container Name: nginxLower Bound:Cpu: 250mMemory: 262144kTarget:Cpu: 250mMemory: 262144kUncapped Target:Cpu: 25mMemory: 262144kUpper Bound:Cpu: 521mMemory: 545693548
Events: <none>
kubectl get event
LAST SEEN TYPE REASON OBJECT MESSAGE
38m Normal Scheduled pod/nginx-59d7c8bd89-q27gc Successfully assigned default/nginx-59d7c8bd89-q27gc to worker02
38m Normal Pulling pod/nginx-59d7c8bd89-q27gc Pulling image "nginx:latest"
38m Normal Pulled pod/nginx-59d7c8bd89-q27gc Successfully pulled image "nginx:latest" in 18.118818504s (18.118826419s including waiting)
38m Normal Created pod/nginx-59d7c8bd89-q27gc Created container nginx
38m Normal Started pod/nginx-59d7c8bd89-q27gc Started container nginx
11m Normal Killing pod/nginx-59d7c8bd89-q27gc Stopping container nginx
38m Normal Scheduled pod/nginx-59d7c8bd89-qb4p4 Successfully assigned default/nginx-59d7c8bd89-qb4p4 to worker01
38m Normal Pulling pod/nginx-59d7c8bd89-qb4p4 Pulling image "nginx:latest"
38m Normal Pulled pod/nginx-59d7c8bd89-qb4p4 Successfully pulled image "nginx:latest" in 17.842596583s (17.842603536s including waiting)
38m Normal Created pod/nginx-59d7c8bd89-qb4p4 Created container nginx
38m Normal Started pod/nginx-59d7c8bd89-qb4p4 Started container nginx
11m Normal Killing pod/nginx-59d7c8bd89-qb4p4 Stopping container nginx
38m Normal SuccessfulCreate replicaset/nginx-59d7c8bd89 Created pod: nginx-59d7c8bd89-q27gc
38m Normal SuccessfulCreate replicaset/nginx-59d7c8bd89 Created pod: nginx-59d7c8bd89-qb4p4
11m Normal Scheduled pod/nginx-6f78fbb759-hcbc6 Successfully assigned default/nginx-6f78fbb759-hcbc6 to worker02
11m Normal Pulled pod/nginx-6f78fbb759-hcbc6 Container image "nginx:latest" already present on machine
11m Normal Created pod/nginx-6f78fbb759-hcbc6 Created container nginx
11m Normal Started pod/nginx-6f78fbb759-hcbc6 Started container nginx
10m Normal Killing pod/nginx-6f78fbb759-hcbc6 Stopping container nginx
9m51s Normal Scheduled pod/nginx-6f78fbb759-jhf7h Successfully assigned default/nginx-6f78fbb759-jhf7h to worker02
9m51s Normal Pulled pod/nginx-6f78fbb759-jhf7h Container image "nginx:latest" already present on machine
9m51s Normal Created pod/nginx-6f78fbb759-jhf7h Created container nginx
9m51s Normal Started pod/nginx-6f78fbb759-jhf7h Started container nginx
6m31s Normal Killing pod/nginx-6f78fbb759-jhf7h Stopping container nginx
6m31s Normal EvictedByVPA pod/nginx-6f78fbb759-jhf7h Pod was evicted by VPA Updater to apply resource recommendation.
6m30s Normal Scheduled pod/nginx-6f78fbb759-mcppm Successfully assigned default/nginx-6f78fbb759-mcppm to worker02
6m30s Normal Pulled pod/nginx-6f78fbb759-mcppm Container image "nginx:latest" already present on machine
6m30s Normal Created pod/nginx-6f78fbb759-mcppm Created container nginx
6m30s Normal Started pod/nginx-6f78fbb759-mcppm Started container nginx
9m51s Normal Scheduled pod/nginx-6f78fbb759-s4xzm Successfully assigned default/nginx-6f78fbb759-s4xzm to worker01
9m51s Normal Pulled pod/nginx-6f78fbb759-s4xzm Container image "nginx:latest" already present on machine
9m51s Normal Created pod/nginx-6f78fbb759-s4xzm Created container nginx
9m51s Normal Started pod/nginx-6f78fbb759-s4xzm Started container nginx
7m31s Normal EvictedByVPA pod/nginx-6f78fbb759-s4xzm Pod was evicted by VPA Updater to apply resource recommendation.
7m31s Normal Killing pod/nginx-6f78fbb759-s4xzm Stopping container nginx
7m30s Normal Scheduled pod/nginx-6f78fbb759-x986h Successfully assigned default/nginx-6f78fbb759-x986h to worker01
7m30s Normal Pulled pod/nginx-6f78fbb759-x986h Container image "nginx:latest" already present on machine
7m30s Normal Created pod/nginx-6f78fbb759-x986h Created container nginx
7m30s Normal Started pod/nginx-6f78fbb759-x986h Started container nginx
11m Normal Scheduled pod/nginx-6f78fbb759-z4sxb Successfully assigned default/nginx-6f78fbb759-z4sxb to worker01
11m Normal Pulled pod/nginx-6f78fbb759-z4sxb Container image "nginx:latest" already present on machine
11m Normal Created pod/nginx-6f78fbb759-z4sxb Created container nginx
11m Normal Started pod/nginx-6f78fbb759-z4sxb Started container nginx
10m Normal Killing pod/nginx-6f78fbb759-z4sxb Stopping container nginx
11m Normal SuccessfulCreate replicaset/nginx-6f78fbb759 Created pod: nginx-6f78fbb759-hcbc6
11m Normal SuccessfulCreate replicaset/nginx-6f78fbb759 Created pod: nginx-6f78fbb759-z4sxb
9m52s Normal SuccessfulCreate replicaset/nginx-6f78fbb759 Created pod: nginx-6f78fbb759-jhf7h
9m52s Normal SuccessfulCreate replicaset/nginx-6f78fbb759 Created pod: nginx-6f78fbb759-s4xzm
7m31s Normal SuccessfulCreate replicaset/nginx-6f78fbb759 Created pod: nginx-6f78fbb759-x986h
6m31s Normal SuccessfulCreate replicaset/nginx-6f78fbb759 Created pod: nginx-6f78fbb759-mcppm
38m Normal ScalingReplicaSet deployment/nginx Scaled up replica set nginx-59d7c8bd89 to 2
11m Normal ScalingReplicaSet deployment/nginx Scaled up replica set nginx-6f78fbb759 to 2
10m Warning FailedToUpdateEndpoint endpoints/nginx Failed to update endpoint default/nginx: Operation cannot be fulfilled on endpoints "nginx": the object has been modified; please apply your changes to the latest version and try again
9m52s Normal ScalingReplicaSet deployment/nginx Scaled up replica set nginx-6f78fbb759 to 2
从输出信息可以了解到，vpa执行了EvictedByVPA，自动停掉了nginx，然后使用 VPA推荐的资源启动了新的nginx，我们查看下nginx的pod可以得到确认
kubectl describe pods nginx-6f78fbb759-mcppm
Name: nginx-6f78fbb759-mcppm
Namespace: default
Priority: 0
Service Account: default
Node: worker02/192.168.10.13
Start Time: Sun, 09 Jun 2024 19:29:09 +0800
Labels: app=nginxpod-template-hash=6f78fbb759
Annotations: cni.projectcalico.org/containerID: 145e1f8509982da00e61eb180bb9f3b52e527bc94d8657237d340fd9bf01475acni.projectcalico.org/podIP: 10.244.30.72/32cni.projectcalico.org/podIPs: 10.244.30.72/32vpaObservedContainers: nginxvpaUpdates: Pod resources updated by nginx-vpa-auto: container 0: cpu request, memory request
Status: Running
IP: 10.244.30.72
IPs:IP: 10.244.30.72
Controlled By: ReplicaSet/nginx-6f78fbb759
Containers:nginx:Container ID: docker://97f865221289a48d042dfd039b2eb33876c2d08a89c2f7863fd7e42b5f7f8018Image: nginx:latestImage ID: docker-pullable://nginx@sha256:0f04e4f646a3f14bf31d8bc8d885b6c951fdcf42589d06845f64d18aec6a3c4dPort: <none>Host Port: <none>State: RunningStarted: Sun, 09 Jun 2024 19:29:10 +0800Ready: TrueRestart Count: 0Requests:cpu: 250mmemory: 262144kEnvironment: <none>Mounts:/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-gfzhm (ro)
Conditions:Type StatusInitialized True Ready True ContainersReady True PodScheduled True
Volumes:kube-api-access-gfzhm:Type: Projected (a volume that contains injected data from multiple sources)TokenExpirationSeconds: 3607ConfigMapName: kube-root-ca.crtConfigMapOptional: <nil>DownwardAPI: true
QoS Class: Burstable
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300snode.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:Type Reason Age From Message---- ------ ---- ---- -------Normal Scheduled 8m56s default-scheduler Successfully assigned default/nginx-6f78fbb759-mcppm to worker02Normal Pulled 8m56s kubelet Container image "nginx:latest" already present on machineNormal Created 8m56s kubelet Created container nginxNormal Started 8m56s kubelet Started container nginx
随着服务的负载的变化，VPA的推荐值也会不断变化。当目前运行的pod的资源达不到VPA的推荐值，就会执行pod驱逐，重新部署新的足够资源的服务。
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