From ce3d94af1aa0724e2a0ad3f5ce715a6e30ccd707 Mon Sep 17 00:00:00 2001 From: Evan Lezar Date: Tue, 8 Nov 2022 15:15:27 +0100 Subject: [PATCH] Add README for generating CDI specifications Signed-off-by: Evan Lezar --- cmd/nvidia-ctk/README.md | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/cmd/nvidia-ctk/README.md b/cmd/nvidia-ctk/README.md index 6a94a082..b6186819 100644 --- a/cmd/nvidia-ctk/README.md +++ b/cmd/nvidia-ctk/README.md @@ -15,3 +15,34 @@ nvidia-ctk runtime configure --set-as-default ``` will ensure that the NVIDIA Container Runtime is added as the default runtime to the default container engine. + +### Generate CDI specifications + +The [Container Device Interface (CDI)](https://github.com/container-orchestrated-devices/container-device-interface) provides +a vendor-agnostic mechanism to make arbitrary devices accessible in containerized environments. To allow NVIDIA devices to be +used in these environments, the NVIDIA Container Toolkit CLI includes functionality to generate a CDI specification for the +available NVIDIA GPUs in a system. + +In order to generate the CDI specification for the available devices, run the following command:\ +```bash +nvidia-ctk cdi generate +``` + +The default is to print the specification to STDOUT and a filename can be specified using the `--output` flag. + +The specification will contain a device entries as follows (where applicable): +* An `nvidia.com/gpu=gpu{INDEX}` device for each non-MIG-enabled full GPU in the system +* An `nvidia.com/gpu=mig{GPU_INDEX}:{MIG_INDEX}` device for each MIG-device in the system +* A special device called `nvidia.com/gpu=all` which represents all available devices. + +For example, to generate the CDI specification in the default location where CDI-enabled tools such as `podman`, `containerd`, `cri-o`, or the NVIDIA Container Runtime can be configured to load it, the following command can be run: + +```bash +sudo nvidia-ctk cdi generate --output=/etc/cdi/nvidia.yaml +``` +(Note that `sudo` is used to ensure the correct permissions to write to the `/etc/cdi` folder) + +With the specification generated, a GPU can be requested by specifying the fully-qualified CDI device name. With `podman` as an exmaple: +```bash +podman run --rm -ti --device=nvidia.com/gpu=gpu0 ubuntu nvidia-smi -L +```