Distributed Operating Systems Based on a Protected Global Virtual Address Space

With the advent of the 64bit microprocessor, the virtual address space supported by a workstation will be large enough to permit the use of a single shared address space spanning a network of workstations as the primary abstraction provided by a distributed operating system. In such a system, built upon a software distributed shared memory, the programmer has considerable flexibility when choosing a mechanism for interprocess communication. This flexibility permits the programmer to make a case-by-case choice between simplicity and performance when both goals are not simultaneously achievable. With the inclusion of mechanisms supporting protection and fault tolerance, we believe that such a system can provide the advantages of conventional message-based distributed operating systems (e.g., multiple protection domains, hidden data abstractions, simple client-server interface, and failure isolation), in addition to several other benefits (e.g., easy sharing of complex data structures between processes, transparent replication of server functions, and a uniform interface for all communication).