Evolving Linux SMB3.1.1: Faster, Safer, More Scalable File Access

Accessing remote storage from Linux over SMB3.1.1 continues to evolve rapidly. This session explores the latest advancements in the Linux SMB3.1.1 client, delivering faster, more secure, and more efficient access to a broad ecosystem of SMB file servers, including Samba, Microsoft Azure Files (the "largest file server in the world"), ksmbd, Windows Server, NetApp storage systems, and MacOS.

The talk will cover recent improvements in performance, security, scalability, and Linux integration. Highlights include smarter use of directory leases, faster directory enumeration, enhanced data caching through netfs improvements, multichannel improvements, networking optimizations, and expanded support for SMB3.1.1 compression. POSIX compatibility continues to improve, with new support for tmpfile creation, enhanced swap-file support over SMB3.1.1 mounts, and additional Linux system call support.

Security enhancements include new authentication mechanisms and support for SMB3.1.1 over QUIC.

This session will also examine the rapid evolution of SMBDirect (SMB over RDMA). The new smbdirect.ko infrastructure simplifies deployment of high-performance RDMA transports across the Linux SMB client, the in-kernel SMB server (ksmbd.ko), and userspace applications such as Samba and related tooling.

In addition, the presentation highlights recent progress in the in-kernel SMB server, ksmbd, which continues to gain functionality, performance, and improved quality, making it increasingly useful for lightweight servers, embedded systems, containerized environments, as well as development, and testing scenarios.

The Linux SMB3.1.1 client remains one of the most actively developed filesystems in the Linux kernel, with substantial parallel evolution in userspace tooling and server integration. Attendees will leave with a practical understanding of how to apply these new capabilities to real-world workloads, along with a preview of upcoming SMB3.1.1 enhancements planned for Linux.