Microsoft has unveiled a “state of the art” file system for the next 10 years that builds on NTFS.
Named Resilient File System (ReFS), Microsoft’s latest baby will be delivered with Windows 8 Server and become the foundation of storage on Windows Clients.
ReFS will be used with Windows 8’s Storage Spaces, a feature in Microsoft’s forthcoming Windows 8 Client that pools storage for use by different machines. Storage Spaces and ReFS have been designed to complement each other as components of a “complete storage system”.
“We believe this significantly advances our state of the art for storage,” Windows storage and file system development manager Surendra Verma wrote Monday on the Building Windows 8 blog. Verma wrote:
We will implement ReFS in a staged evolution of the feature: first as a storage system for Windows Server, then as storage for clients, and then ultimately as a boot volume. This is the same approach we have used with new file systems in the past.
NTFS was introduced by Microsoft in Windows NT in 1993 and has penetrated deep into computing. Verma and his boss, Windows group president Steven Sinofsky, stressed that ReFS does not replace NTFS and that it builds on the existing system. ReFS reuses NTFS code responsible for the Windows file system semantics, Verma said.
“This code implements the file system interface (read, write, open, close, change notification, etc), maintains in-memory file and volume state, enforces security, and maintains memory caching and synchronization for file data. This reuse ensures a high degree of compatibility with the features of NTFS that we’re carrying forward,” he wrote.
The difference between ReFS and NTFS is that the code uses a new engine to implement on-disk structures, such as the Master File Table, to represent files and directories. It’s this machinery, Verma wrote, “where a significant portion of the innovation behind ReFS lies”.
By working with Storage Spaces, ReFS tries to protect data from partial and complete disk failures, and will remove data from the name space on a live volume where information has been corrupted. Meanwhile a process has been added that periodically scrubs metadata and Integrity Stream data on volumes living on a mirrored Storage Space.
The initial focus of ReFS will be on its role in file servers, especially with mirrored Storage Spaces. “We also plan to work with our storage partners to integrate it with their storage solutions,” Verma wrote.
The overall thinking of ReFS seems to be data and file management and a recovery system built from the ground up for peers and nodes of all sizes while handling increasing quantities of big data. NTFS dates from a time when departmental-level and LAN-levels of scale inside the corporate firewall were the goal. ®