fistgen

This software review is about a revolutionary solution to file system development problems. Building file systems is known to be a difficult and time-consuming task. Even minor modifications to existing file systems require a deep understanding of kernel internals, making it challenging for new developers to start working on them. Additionally, porting file system code from one operating system to another is almost as challenging as the first port.

While previous attempts have been made to facilitate the development of new file systems through extensible file system interfaces, these proposals required significant changes to both operating system interfaces and existing file systems, which caused resistance from operating system vendors and maintainers who prioritized stability and performance.

Enter the FiST (File System Translator) system, which combines two methods to resolve these issues in a new and innovative way. They use a set of stackable file system templates for each operating system and a high-level language to describe stackable file systems in a cross-platform portable manner. With FiST, stackable file systems only need to be described once. The code generation tool, fistgen, compiles this single file system description into loadable kernel modules for different operating systems such as Solaris, Linux, and FreeBSD.

Using FiST, developers can benefit from significant reductions in code size and development time while imposing only a small performance overhead of 1-2%. Furthermore, FiST ensures portability without making any drastic changes to existing operating systems or file systems.

In conclusion, FiST is a highly effective and innovative software for file system developers looking for a solution to the difficulties and limitations of traditional methods. By combining stackable file system templates and a portable language, FiST significantly reduces complexity, code size, and development time, leading to a more efficient and effective software development process.