The Mach kernel

Mach is an operating system kernel developed at Carnegie-Mellon University to support operating system research, primarily distributed and parallel computation. The Mach operating system was designed to incorporate the many recent innovations in operating system research to produce a technically advanced and fully functional system. Mach incorporates multiprocessing support throughout which is extremely flexible and ranges from shared memory systems to systems with no memory shared between processors. Mach provides a new foundation for UNIX development that spans networks of uniprocessors and multiprocessors. This paper describes Mach and its design. Also described are some of the details of its implementation and current status.