Efficient, protected extension of commodity operating systems
Douglas P. Ghormley, Thomas E. Anderson · 1998
Efficient, Protected Extension of Commodity Operating Systems by Douglas Phillip Ghormley Doctor of Philosophy in Computer Science University of California, Berkeley Professor Thomas Anderson, Chair A network of workstations, harnessed as a single, coherent cluster, offers significant advantages in terms of scalability, cost/performance, incremental growth, and fault tolerance. Effectively extending UNIX semantics from a single node to a cluster requires a level of virtualization for existing UNIX abstractions. Prior efforts to add a level of virtualization in the kernel suffer from many disadvantages, including high cost, implementation complexity, and lack of portability; efforts to virtualize at the user level suffer from restrictions on possible functionality and either lack protection or limited performance. This dissertation examines these problems through the real-world example of GLUnix, a user-level layer providing cluster functionality to a network of workstations.