# Dynamic Resource Allocation 相关知识请参阅 Kubernetes 官网文档 , 目前是 1.34 版本。 ## Kubernetes 1.32 请参阅 Kubernetes 官网文档 . `DynamicResourceAllocation` 在 Kubernetes 1.32 上为 beta 特性，需要额外参数启用。如果集群是用 `kubeadm` 安装的，控制平面运行在 Pod 里，可用以下命令检查： ```console $ kubectl get po -n kube-system -l tier=control-plane NAME READY STATUS RESTARTS AGE etcd-las0 1/1 Running 3 (23d ago) 177d kube-apiserver-las0 1/1 Running 0 23h kube-controller-manager-las0 1/1 Running 1 (23h ago) 23h kube-scheduler-las0 1/1 Running 0 23h ``` 这种情况下，需要在所有控制平面节点上修改以下三个文件： 1. `/etc/kubernetes/manifests/kube-apiserver.yaml` :::{literalinclude} /_files/ubuntu/etc/kubernetes/manifests/kube-apiserver.yaml :diff: /_files/ubuntu/etc/kubernetes/manifests/kube-apiserver.yaml.orig ::: 2. `/etc/kubernetes/manifests/kube-controller-manager.yaml` :::{literalinclude} /_files/ubuntu/etc/kubernetes/manifests/kube-controller-manager.yaml :diff: /_files/ubuntu/etc/kubernetes/manifests/kube-controller-manager.yaml.orig ::: 3. `/etc/kubernetes/manifests/kube-scheduler.yaml` :::{literalinclude} /_files/ubuntu/etc/kubernetes/manifests/kube-scheduler.yaml :diff: /_files/ubuntu/etc/kubernetes/manifests/kube-scheduler.yaml.orig ::: 修改完成后相关的 Pod 会自动重启。 ### 安装 dra-example-driver `dra-example-driver` 是一个 DRA 设备驱动的 DEMO. 下载源码： ```console $ git clone git@github.com:kubernetes-sigs/dra-example-driver.git ``` 构建驱动（使用 docker 需要设置环境变量） ```console $ cd dra-example-driver/ $ CONTAINER_TOOL=docker ./demo/build-driver.sh ``` 使用 `helm` 部署到集群： ```console $ helm upgrade -i --create-namespace --namespace dra-example-driver dra-example-driver deployments/helm/dra-example-driver Release "dra-example-driver" does not exist. Installing it now. NAME: dra-example-driver LAST DEPLOYED: Tue Nov 4 17:45:05 2025 NAMESPACE: dra-example-driver STATUS: deployed REVISION: 1 TEST SUITE: None ``` 查看其 Workloads: ```console $ kubectl get all -n dra-example-driver NAME READY STATUS RESTARTS AGE pod/dra-example-driver-kubeletplugin-67x59 1/1 Running 0 3m53s pod/dra-example-driver-kubeletplugin-j2bl2 1/1 Running 0 3m53s pod/dra-example-driver-kubeletplugin-ndsw9 1/1 Running 0 3m53s NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE daemonset.apps/dra-example-driver-kubeletplugin 3 3 3 3 3 3m53s ``` 查看生成的 ResourcesSlices 和 DeviceClasses: ```console $ kubectl get resourceslice NAME NODE DRIVER POOL AGE las1-gpu.example.com-n297b las1 gpu.example.com las1 4m8s las2-gpu.example.com-tpwcb las2 gpu.example.com las2 4m18s las3-gpu.example.com-m4zn4 las3 gpu.example.com las3 4m22s $ kubectl get deviceclasses NAME AGE gpu.example.com 7m39s ``` 进一步查看 ResourceSlice 的说明： ```console $ kdesc resourceslice las1-gpu.example.com-n297b Name: las1-gpu.example.com-n297b Namespace: Labels: Annotations: API Version: resource.k8s.io/v1beta1 Kind: ResourceSlice ... Spec: Devices: Basic: Attributes: Driver Version: Version: 1.0.0 Index: Int: 0 Model: String: LATEST-GPU-MODEL Uuid: String: gpu-94011f0b-8dcd-b4b0-cd99-40eab2e3c96a Capacity: Memory: Value: 80Gi Name: gpu-0 ... ``` 可以看到生成了名为 `gpu-*` 的设备（实际上每个节点上有 8 个）。 :::{note} 驱动卸载时没有删除 ResourceSlices. 用以下命令删除： ```console $ kubectl delete resourceslice --field-selector spec.driver=gpu.example.com resourceslice.resource.k8s.io "las1-gpu.example.com-n297b" deleted resourceslice.resource.k8s.io "las2-gpu.example.com-tpwcb" deleted resourceslice.resource.k8s.io "las3-gpu.example.com-m4zn4" deleted ``` ::: ### 测试 在集群内创建一个 ResourceClaimTemplate: ```console $ kubectl apply -f example_resourceclaimtemplate.yaml resourceclaimtemplate.resource.k8s.io/example created ``` 其定义如下： :::{literalinclude} /_files/macos/workspace/k8s/dra/example_resourceclaimtemplate.yaml ::: 再创建一个 Pod 进行测试。Pod 的定义如下： :::{literalinclude} /_files/macos/workspace/k8s/dra/example_claim_po.yaml ::: 创建 Pod 时可以监视 ResourceClaim 资源的变化： ```console $ kubectl get resourceclaim -w NAME STATE AGE example-claim-example-4cb2t pending 0s example-claim-example-4cb2t pending 0s example-claim-example-4cb2t allocated,reserved 0s example-claim-example-4cb2t pending 63s example-claim-example-4cb2t pending 63s example-claim-example-4cb2t pending 63s ``` 这种自动生成的 ResourceClaim 的所有者是这个 Pod, 当 Pod 被删除时它也被删除。 ## Kubernetes 1.34 把集群升级到 1.34: ```console $ kubectl get no NAME STATUS ROLES AGE VERSION las0 Ready control-plane 189d v1.34.2 las1 Ready 189d v1.34.2 las2 Ready 189d v1.34.2 las3 Ready 185d v1.34.2 ``` `DynamicResourceAllocation` 特性在 Kubernetes 1.34 上默认启用，所以之前的额外参数可以去掉，但别忘了升级服务映像的版本： 1. `/etc/kubernetes/manifests/kube-apiserver.yaml` :::{literalinclude} /_files/ubuntu/etc/kubernetes/manifests/kube-apiserver_1.34.yaml :diff: /_files/ubuntu/etc/kubernetes/manifests/kube-apiserver.yaml.orig ::: 2. `/etc/kubernetes/manifests/kube-controller-manager.yaml` :::{literalinclude} /_files/ubuntu/etc/kubernetes/manifests/kube-controller-manager_1.34.yaml :diff: /_files/ubuntu/etc/kubernetes/manifests/kube-controller-manager.yaml.orig ::: 3. `/etc/kubernetes/manifests/kube-scheduler.yaml` :::{literalinclude} /_files/ubuntu/etc/kubernetes/manifests/kube-scheduler_1.34.yaml :diff: /_files/ubuntu/etc/kubernetes/manifests/kube-scheduler.yaml.orig ::: 检查 API 版本以确认： ```console $ kubectl api-versions | grep resource.k8s.io resource.k8s.io/v1 ``` 重新安装 dra-example-driver. ResourceClaimTemplate 需要修改： :::{literalinclude} /_files/macos/workspace/k8s/dra/example_resourceclaimtemplate_1.34.yaml :diff: /_files/macos/workspace/k8s/dra/example_resourceclaimtemplate.yaml ::: 原来的对应字段被挪到了 `exactly` 下面。`exactly` 可以变为 `firstAvailable`, 其下可以放置一个列表以提供备选。 Pod 的定义不需要任何修改。