NFSv4.2 support (Server-Side Copy) in Windows NFS Server

[unxed]

I’d like to request support for NFSv4.2, specifically Server-Side Copy (COPY offload) as defined in RFC 7862, in the Windows NFS Server.

This feature enables true server-side file copy operations, which dramatically improves performance when working with files over NFS, because data is copied entirely on the server without being transferred through the client.

Real-world use case: a number of far2l users work inside WSL and need fast, native-speed access to the Windows host filesystem.

Without NFSv4.2 server-side copy, operations like copying or moving large files are limited by server-client throughput and CPU usage. With copy offload, these operations become nearly as fast as native filesystem operations on the host.

Why this matters in practice:

There are already users who deliberately choose far2l running inside WSL instead of Far Manager 3 on Windows, even on Windows systems, because far2l provides features they care about (for example, proper word wrap in the editor and other advanced behaviors).

For these users, high-performance filesystem access between WSL and the Windows host is critical. NFSv4.2 with server-side copy would be an ideal solution and would significantly improve their workflow.

Thank you for considering this request.

[github-actions]

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[unxed]

/feature

[github-actions]

Diagnostic information

Found '/feature', adding tag 'feature'

[unxed]

Better use SMB for what.