Linux 5.5 Adds NFS Client Support For Cross-Device Offloaded Copies (Server To Server)

With NFSv4.2 is the server-side copy (SSC) functionality with the Linux 5.5 kernel's NFS client-side support for that support in allowing "inter" copy offloads between different NFS servers.

This support allows for server-to-server efficient file copies with NFSv4.2 SSC rather than first having to copy to the client system. The NFS client changes also introduce new RDMA tracepoints for debugging congestion control and various other fixes.

For those wondering about other Linux NFSv4.2 features can see this Red Hat slide deck covering other work as of 2018.