This repository contains an example resource driver for use with the Dynamic Resource Allocation (DRA) feature of Kubernetes.
It is intended to demonstrate best-practices for how to construct a DRA resource driver and wrap it in a helm chart. It can be used as a starting point for implementing a driver for your own set of resources.
Before diving into the details of how this example driver is constructed, it's useful to run through a quick demo of it in action.
The driver itself provides access to a set of mock GPU devices, and this demo walks through the process of building and installing the driver followed by running a set of workloads that consume these GPUs.
The procedure below has been tested and verified on both Linux and Mac.
- GNU Make 3.81+
- GNU Tar 1.34+
- docker v20.10+ (including buildx) or Podman v4.9+
- kind v0.17.0+
- helm v3.7.0+
- kubectl v1.18+
We start by first cloning this repository and cd
ing into it. All of the
scripts and example Pod specs used in this demo are contained here, so take a
moment to browse through the various files and see what's available:
git clone https://github.com/kubernetes-sigs/dra-example-driver.git
cd dra-example-driver
Note: The scripts will automatically use either docker
, or podman
as the container tool command, whichever
can be found in the PATH. To override this behavior, set CONTAINER_TOOL
environment variable either by calling
export CONTAINER_TOOL=docker
, or by prepending CONTAINER_TOOL=docker
to a script
(e.g. CONTAINER_TOOL=docker ./path/to/script.sh
). Keep in mind that building Kind images currently requires Docker.
From here we will build the image for the example resource driver:
./demo/build-driver.sh
And create a kind
cluster to run it in:
./demo/create-cluster.sh
Once the cluster has been created successfully, double check everything is coming up as expected:
$ kubectl get pod -A
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-5d78c9869d-6jrx9 1/1 Running 0 1m
kube-system coredns-5d78c9869d-dpr8p 1/1 Running 0 1m
kube-system etcd-dra-example-driver-cluster-control-plane 1/1 Running 0 1m
kube-system kindnet-g88bv 1/1 Running 0 1m
kube-system kindnet-msp95 1/1 Running 0 1m
kube-system kube-apiserver-dra-example-driver-cluster-control-plane 1/1 Running 0 1m
kube-system kube-controller-manager-dra-example-driver-cluster-control-plane 1/1 Running 0 1m
kube-system kube-proxy-kgz4z 1/1 Running 0 1m
kube-system kube-proxy-x6fnd 1/1 Running 0 1m
kube-system kube-scheduler-dra-example-driver-cluster-control-plane 1/1 Running 0 1m
local-path-storage local-path-provisioner-7dbf974f64-9jmc7 1/1 Running 0 1m
And then install the example resource driver via helm
.
helm upgrade -i \
--create-namespace \
--namespace dra-example-driver \
dra-example-driver \
deployments/helm/dra-example-driver
Double check the driver components have come up successfully:
$ kubectl get pod -n dra-example-driver
NAME READY STATUS RESTARTS AGE
dra-example-driver-kubeletplugin-qwmbl 1/1 Running 0 1m
And show the initial state of available GPU devices on the worker node:
$ kubectl get resourceslice -o yaml
apiVersion: v1
items:
- apiVersion: resource.k8s.io/v1alpha3
kind: ResourceSlice
metadata:
creationTimestamp: "2024-07-16T13:00:06Z"
generateName: dra-example-driver-cluster-worker-gpu.example.com-
generation: 1
name: dra-example-driver-cluster-worker-gpu.example.com-xhsqf
ownerReferences:
- apiVersion: v1
controller: true
kind: Node
name: dra-example-driver-cluster-worker
uid: 8a18f216-bd77-426a-86b1-a989bdacc135
resourceVersion: "854"
uid: ea955e01-eaf0-45ed-8a36-1c56e4b8bced
spec:
driver: gpu.example.com
nodeName: dra-example-driver-cluster-worker
pool:
generation: 0
name: dra-example-driver-cluster-worker
resourceSliceCount: 1
devices:
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 0
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-18db0e85-99e9-c746-8531-ffeb86328b39
capacity:
memory: 80Gi
name: gpu-0
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 1
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-93d37703-997c-c46f-a531-755e3e0dc2ac
capacity:
memory: 80Gi
name: gpu-1
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 2
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-ee3e4b55-fcda-44b8-0605-64b7a9967744
capacity:
memory: 80Gi
name: gpu-2
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 3
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-9ede7e32-5825-a11b-fa3d-bab6d47e0243
capacity:
memory: 80Gi
name: gpu-3
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 4
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-e7b42cb1-4fd8-91b2-bc77-352a0c1f5747
capacity:
memory: 80Gi
name: gpu-4
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 5
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-f11773a1-5bfb-e48b-3d98-1beb5baaf08e
capacity:
memory: 80Gi
name: gpu-5
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 6
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-0159f35e-99ee-b2b5-74f1-9d18df3f22ac
capacity:
memory: 80Gi
name: gpu-6
- basic:
attributes:
driverVersion:
version: 1.0.0
index:
int: 7
model:
string: LATEST-GPU-MODEL
uuid:
string: gpu-657bd2e7-f5c2-a7f2-fbaa-0d1cdc32f81b
capacity:
memory: 80Gi
name: gpu-7
kind: List
metadata:
resourceVersion: ""
Next, deploy four example apps that demonstrate how ResourceClaim
s,
ResourceClaimTemplate
s, and custom GpuConfig
objects can be used to
select and configure resources in various ways:
kubectl apply --filename=demo/gpu-test{1,2,3,4,5}.yaml
And verify that they are coming up successfully:
$ kubectl get pod -A
NAMESPACE NAME READY STATUS RESTARTS AGE
...
gpu-test1 pod0 0/1 Pending 0 2s
gpu-test1 pod1 0/1 Pending 0 2s
gpu-test2 pod0 0/2 Pending 0 2s
gpu-test3 pod0 0/1 ContainerCreating 0 2s
gpu-test3 pod1 0/1 ContainerCreating 0 2s
gpu-test4 pod0 0/1 Pending 0 2s
gpu-test5 pod0 0/4 Pending 0 2s
...
Use your favorite editor to look through each of the gpu-test{1,2,3,4,5}.yaml
files and see what they are doing. The semantics of each match the figure
below:
Then dump the logs of each app to verify that GPUs were allocated to them according to these semantics:
for example in $(seq 1 5); do \
echo "gpu-test${example}:"
for pod in $(kubectl get pod -n gpu-test${example} --output=jsonpath='{.items[*].metadata.name}'); do \
for ctr in $(kubectl get pod -n gpu-test${example} ${pod} -o jsonpath='{.spec.containers[*].name}'); do \
echo "${pod} ${ctr}:"
if [ "${example}" -lt 3 ]; then
kubectl logs -n gpu-test${example} ${pod} -c ${ctr}| grep -E "GPU_DEVICE_[0-9]+=" | grep -v "RESOURCE_CLAIM"
else
kubectl logs -n gpu-test${example} ${pod} -c ${ctr}| grep -E "GPU_DEVICE_[0-9]+" | grep -v "RESOURCE_CLAIM"
fi
done
done
echo ""
done
This should produce output similar to the following:
gpu-test1:
pod0 ctr0:
declare -x GPU_DEVICE_6="gpu-6"
pod1 ctr0:
declare -x GPU_DEVICE_7="gpu-7"
gpu-test2:
pod0 ctr0:
declare -x GPU_DEVICE_0="gpu-0"
declare -x GPU_DEVICE_1="gpu-1"
gpu-test3:
pod0 ctr0:
declare -x GPU_DEVICE_2="gpu-2"
declare -x GPU_DEVICE_2_SHARING_STRATEGY="TimeSlicing"
declare -x GPU_DEVICE_2_TIMESLICE_INTERVAL="Default"
pod0 ctr1:
declare -x GPU_DEVICE_2="gpu-2"
declare -x GPU_DEVICE_2_SHARING_STRATEGY="TimeSlicing"
declare -x GPU_DEVICE_2_TIMESLICE_INTERVAL="Default"
gpu-test4:
pod0 ctr0:
declare -x GPU_DEVICE_3="gpu-3"
declare -x GPU_DEVICE_3_SHARING_STRATEGY="TimeSlicing"
declare -x GPU_DEVICE_3_TIMESLICE_INTERVAL="Default"
pod1 ctr0:
declare -x GPU_DEVICE_3="gpu-3"
declare -x GPU_DEVICE_3_SHARING_STRATEGY="TimeSlicing"
declare -x GPU_DEVICE_3_TIMESLICE_INTERVAL="Default"
gpu-test5:
pod0 ts-ctr0:
declare -x GPU_DEVICE_4="gpu-4"
declare -x GPU_DEVICE_4_SHARING_STRATEGY="TimeSlicing"
declare -x GPU_DEVICE_4_TIMESLICE_INTERVAL="Long"
pod0 ts-ctr1:
declare -x GPU_DEVICE_4="gpu-4"
declare -x GPU_DEVICE_4_SHARING_STRATEGY="TimeSlicing"
declare -x GPU_DEVICE_4_TIMESLICE_INTERVAL="Long"
pod0 sp-ctr0:
declare -x GPU_DEVICE_5="gpu-5"
declare -x GPU_DEVICE_5_PARTITION_COUNT="10"
declare -x GPU_DEVICE_5_SHARING_STRATEGY="SpacePartitioning"
pod0 sp-ctr1:
declare -x GPU_DEVICE_5="gpu-5"
declare -x GPU_DEVICE_5_PARTITION_COUNT="10"
declare -x GPU_DEVICE_5_SHARING_STRATEGY="SpacePartitioning"
In this example resource driver, no "actual" GPUs are made available to any containers. Instead, a set of environment variables are set in each container to indicate which GPUs would have been injected into them by a real resource driver and how they would have been configured.
You can use the IDs of the GPUs as well as the GPU sharing settings set in these environment variables to verify that they were handed out in a way consistent with the semantics shown in the figure above.
Once you have verified everything is running correctly, delete all of the example apps:
kubectl delete --wait=false --filename=demo/gpu-test{1,2,3,4,5}.yaml
And wait for them to terminate:
$ kubectl get pod -A
NAMESPACE NAME READY STATUS RESTARTS AGE
...
gpu-test1 pod0 1/1 Terminating 0 31m
gpu-test1 pod1 1/1 Terminating 0 31m
gpu-test2 pod0 2/2 Terminating 0 31m
gpu-test3 pod0 1/1 Terminating 0 31m
gpu-test3 pod1 1/1 Terminating 0 31m
gpu-test4 pod0 1/1 Terminating 0 31m
gpu-test5 pod0 4/4 Terminating 0 31m
...
Finally, you can run the following to cleanup your environment and delete the
kind
cluster started previously:
./demo/delete-cluster.sh
TBD
TBD
TBD
For more information on the DRA Kubernetes feature and developing custom resource drivers, see the following resources:
Learn how to engage with the Kubernetes community on the community page.
You can reach the maintainers of this project at:
Participation in the Kubernetes community is governed by the Kubernetes Code of Conduct.