SNIA Developer Conference September 15-17, 2025 | Santa Clara, CA
Performance Improvements in Samba's Pathname Handling
Abstract
One fallout of Samba's protection against symlink races was a slowdown of pathname handling. This talk will present the current status at the time of the conference of the ongoing work to fix the slowdown by using modern Posix and in particular Linux/FreeBSD APIs.
Learning Objectives
- How to deal with pathnames in posix in a symlink-safe way
- Approaches to performance tests and analysis for pathname handling
- Performance comparison of the different Samba versions over time
Related Sessions
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SMB3 has seen significant adoption as the storage protocol of choice for running private cloud deployments. With the recent advances in persistent memory technologies, we will take a look at how we can leverage the SMB3 protocol in conjunction with SMBDirect/RDMA to provide very low latency access to persistent memory devices across the network. With the increasing popularity of cloud storage - technologies like Azure Files which provide seamless access to cloud stored data via the standard SMB3 protocol is seeing significant interest. One of the key requirements in this space is to be able to run SMB3 over a secure / firewall friendly internet protocol. We will update you on some work we are doing to enable SMB3 over QUIC - which is a recent UDP based transport with strong security and interop properties. We will explore some work we have done to enable on-the-wire compression for SMBDIRECT SMB3. Learning Objectives: 1. Learn how we can use SMB3 to setup direct RDMA access to remote persistent memory 2. Using QUIC as a transport for SMB3 3. How can we use data compression algorithms to optimize SMB data transfer?
The New Samba VFS
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SMB3 Landscape and Directions
SMB3 has seen significant adoption as the storage protocol of choice for running private cloud deployments. In this iteration of the talk, we’ll update the audience on SMB protocol changes as well as improvements to the Windows implementation of the SMB server and client. Added to the SMB protocol is a new server-to-client notification mechanism, which enables a variety of novel use cases. We’ll present the details of protocol messaging (new message types, etc) as well as the one scenario which leverages this new mechanism (server-triggered graceful session closure). In addition to the protocol changes, we’ll provide an overview of the latest feature additions to the Windows SMB server and client: authentication rate limiting to protect against password spray attacks, and upcoming improvements to SMB over QUIC.
Performance Improvements in Samba's Pathname Handling
One fallout of Samba's protection against symlink races was a slowdown of pathname handling. This talk will present the current status at the time of the conference of the ongoing work to fix the slowdown by using modern Posix and in particular Linux/FreeBSD APIs.