docs: add d7y doc link

Signed-off-by: Yan Song <imeoer@linux.alibaba.com>

README.md

@@ -50,7 +50,11 @@ Currently Nydus is supporting the following platforms in container ecosystem:
 | Distribution  | [Dragonfly](https://github.com/dragonflyoss/Dragonfly2)                                                         | Improve the runtime performance of Nydus image even further with the Dragonfly P2P data distribution system                                                  | ✅      |
 | Build         | [Buildkit](https://github.com/moby/buildkit/pull/2581)                                                          | Provides the ability to build and export Nydus images directly from Dockerfile                                                                               | 🚧      |
 | Runtime       | Kubernetes                                                                                                      | Run Nydus image using CRI interface                                                                                                                          | ✅      |
+<<<<<<< Updated upstream
 | Runtime       | [Containerd](https://github.com/containerd/nydus-snapshotter)                                                   | Nydus Snapshotter, a containerd remote plugin to run Nydus image                                                                                             | ✅      |
+=======
+| Runtime       | [Containerd](https://github.com/containerd/nydus-snapshotter)                                                   | Run Nydus image in containerd with nydus-snapshotter                                                                                                         | ✅      |
+>>>>>>> Stashed changes
 | Runtime       | [CRI-O / Podman](https://github.com/containers/nydus-storage-plugin)                                            | Run Nydus image with CRI-O or Podman                                                                                                                         | 🚧      |
 | Runtime       | [Docker](https://github.com/dragonflyoss/image-service/tree/master/contrib/docker-nydus-graphdriver)            | Run Nydus image in Docker container with graphdriver plugin                                                                                                  | ✅      |
 | Build/Runtime | [Nerdctl](https://github.com/containerd/nerdctl/blob/master/docs/nydus.md)                                      | The containerd client to build or run (requires nydus snapshotter) Nydus image                                                                               | ✅      |
@@ -105,6 +109,10 @@ Since [Linux 5.19](https://lwn.net/Articles/896140), EROFS has added a new file-
 
 Guide to running Nydus with fscache: [Nydus-fscache](./docs/nydus-fscache.md)
 
+## Run Nydus with Dragonfly P2P system
+
+Nydus is deeply integrated with [Dragonfly](https://d7y.io/) P2P system, which can greatly reduce the network latency and the single point of network pressure for registry server, testing in the production environment shows that using Dragonfly can reduce network latency by more than 80%, to understand the performance test data and how to configure Nydus to use Dragonfly, please refer to the [doc](https://d7y.io/docs/setup/integration/nydus).
+
 ## Build Images via Harbor
 
 Nydus cooperates with Harbor community to develop [acceleration-service](https://github.com/goharbor/acceleration-service) which provides a general service for Harbor to support image acceleration based on kinds of accelerators like Nydus, eStargz, etc.

docs/containerd-env-setup.md

@@ -216,3 +216,7 @@ $ sudo crictl ps
 CONTAINER ID        IMAGE                                CREATED             STATE               NAME                      ATTEMPT             POD ID
 f4a6c6dc47e34       localhost:5000/ubuntu-nydus:latest   9 seconds ago       Running             nydus-container           0                   21b91779d551e
 ```
+
+## Integrate P2P with Dragonfly
+
+Nydus is deeply integrated with [Dragonfly](https://d7y.io/) P2P system, which can greatly reduce the network latency and the single point of network pressure for registry server, testing in the production environment shows that using Dragonfly can reduce network latency by more than 80%, to understand the performance test data and how to configure Nydus to use Dragonfly, please refer to the [doc](https://d7y.io/docs/setup/integration/nydus).

docs/nydusd.md

@@ -239,9 +239,11 @@ Once the configuration is loaded successfully on nydusd starting, we will see th
 INFO [storage/src/backend/connection.rs:136] backend config: CommonConfig { proxy: ProxyConfig { url: "http://p2p-proxy:65001", ping_url: "http://p2p-proxy:40901/server/ping", fallback: true, check_interval: 5 }, timeout: 5, connect_timeout: 5, retry_limit: 0 }
 ```
 
-##### Enable Mirrors for Storage Backend
+##### Enable Mirrors for Storage Backend (Recommend)
 
-Add `device.backend.config.mirrors` field to enable mirrors for storage backend. The mirror can be a P2P distribution server (such as [Dragonfly](https://d7y.io/)) or registry. If the request to mirror server failed, it will fall back to the original registry.
+Nydus is deeply integrated with [Dragonfly](https://d7y.io/) P2P mirror mode, please refer the [doc](https://d7y.io/docs/setup/integration/nydus) to learn how configuring Nydus to use Dragonfly.
+
+Add `device.backend.config.mirrors` field to enable mirrors for storage backend. The mirror can be a P2P distribution server or registry. If the request to mirror server failed, it will fall back to the original registry.
 Currently, the mirror mode is only tested in the registry backend, and in theory, the OSS backend also supports it.
 
 <font color='red'>!!</font> The `mirrors` field conflicts with `proxy` field.