The Grand Unified Theory of Address Spaces

A key decision in the design of an operating system is which facilities to provide for the management and composition of the address space. A wide spectrum of schemes exist, ranging from the private process ad- dress spaces of Unix through to the recently revived single address space approach. This paper proposes a new model which provides a unified and generalised approach to address space management. The model presents a single abstraction of address spaces which are orthogonal to processes and may be composed in arbitrary ways. The power of the model is demonstrated by case studies which show how shared libraries, a Unix system and a single address space system may be implemented.