UNIVERSITY OF HOUSTON Department of Computer Science COSC 6360--Operating Systems QUALIFYING EXAMINATION Graduate Part FINAL EXAMINATION Part I May 8, 1995 This exam is closed book. You can have two sheet of notes. 1. How would you modify the Sprite file system to let client caches directly cooperate with each other? What would be the major advantages and disadvantages of your solution? (20 points) 2. There are now workstations having 64 bit addresses. This is big enough to give every living human his or her own Gigabyte of data in the address space of every process! Discuss the impact of very large address spaces on operating systems and indicate a few possible changes in the way things are done today. (20 points) UNIVERSITY OF HOUSTON Department of Computer Science COSC 6360--Operating Systems FINAL EXAMINATION Part II May 8, 1995 This exam is closed book. You can have two sheet of notes. 1. What mechanism does AMOEBA use to allow owners of a capability to construct a new capability with a subset of the rights of that capability? (10 points) 2. According to L. Lamport, what is the major disadvantage of logical clocks? (10 points) 3. Which mechanisms are used by Grapevine to let a new client locate its first Grapevine server? (10 points) 4. Explain the mechanism used by Coda to detect inconsistencies between different replicas of the same file. (10 points) 5. Contrast and compare Sprite prefix tables with NFS remote mount mechanism. (10 points) 6. What is the major advantage of a log-structured file system? (5 points) 7. What is the only serious advantage of stateless file servers? (5 points)