The File System Belongs in the Kernel.
Brent B. Welch · 1991
This paper argues that a shared, distributed name space and I/O interface should be implemented inside the operating system kernel. The grounding for the argument is a comparison between the Sprite network operating system and the Mach microkernel. Sprite optimizes the common case of file and device access, both local and remote, by providing a kernel-level implementation. Sprite also allows for user-level extensibility by letting a user-level process implement the naming and I/O interfaces of the file system. Mach, in contrast, provide general interprocess communication and does not define a file system protocol in the kernel. [Published in the Proceedings of the 2nd USENIX Mach Symposium, Nov 20-22, 1991, pages 233250 ] 1 Introduction This paper argues that the file system is a mature enough abstraction that it should be implemented inside the operating system kernel for optimal performance. Data storage and high-level naming are fundamental features of today's computer syste...