Add instructions for configuring nvidia-container-runtime with contai…

…nerd.

The only way to get containerd to use runsc shim correctly alongside
nvidia-container-runtime right now is to manually modify
/etc/containerd/config.toml after running `nvidia-ctk runtime configure` and
updating `plugins."io.containerd.grpc.v1.cri".containerd.runtimes.nvidia` =>
`runtime_type` to "io.containerd.runsc.v1".

See #10997 (comment).

Fixes #10997

PiperOrigin-RevId: 687431610

g3doc/user_guide/containerd/configuration.md

@@ -100,3 +100,26 @@ log_level = "debug"
   debug-log = "/var/log/runsc/%ID%/gvisor.%COMMAND%.log"
 EOF
 ```
+
+### NVIDIA Container Runtime
+
+If you want to use
+[`nvidia-container-runtime`](https://developer.nvidia.com/container-runtime)
+with runsc through containerd, you might need to configure `nvidia` runtime in
+containerd via `sudo nvidia-ctk runtime configure --runtime=containerd` command.
+This will update `/etc/containerd/config.toml` with a new runtime named
+`nvidia`. However, it defaults to setting its `runtime_type` to runc. You will
+need to manually update this field to specify runsc so that containerd tries to
+invoke `containerd-shim-runsc-v1` when using `nvidia` runtime. The
+`/etc/containerd/config.toml` file should look like:
+
+```
+...
+[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.nvidia]
+  runtime_type = "io.containerd.runsc.v1"
+...
+```
+
+See [this section](../gpu.md#nvidia-container-runtime) for information about
+configuring `nvidia-container-runtime` to use `runsc` as its low-level runtime.
+```