A disk head scheduling simulator

ABSTRACT

Disk head scheduling is a standard topic in undergraduate operating systems courses. Disk drives were once fairly simple devices with little intelligence. Disk head scheduling and bad block mapping were done exclusively by operating systems. As disk drives became larger and faster, they took on some of these tasks. Modern drives often have a large cache and hide their internal structure from the outside world. In spite of changes in disk technology, the teaching of disk head scheduling has changed little over the last decade. This paper describes a disk head scheduling simulator that allows students to explore traditional disk scheduling algorithms as well as the consequences of modern disk technology. The simulator, which is written in Java and is freely available, can be run remotely from a browser or downloaded for local execution. We present methods for modifying the traditional curriculum to make the presentation of disk head scheduling more relevant and interesting.

REFERENCES

• 1: Denning, P. J., "Effects of scheduling on file memory operations," AFIPS Spring Joint Computer Conference, April 1967, pp. 9--21.
• 2: Gary J. Nutt, Operating Systems: A Modern Perspective, Addison-Wesley Longman Publishing Co., Inc., Boston, MA, 1999
• 3: SOURCE Robbins, S., A disk head scheduling simulator, 2003. Online. Internet. Available WWW: \httpfont http://vip.cs.utsa.edu/nsf/disk/
• 4: Abraham Silberschatz , Peter Galvin , Greg Gagne, Applied Operating System Concepts, John Wiley & Sons, Inc., New York, NY, 2001
• 5: Stallings, W., Operating Systems, Second Edition, Prentice Hall, 1995.
• 6: Andrew S. Tanenbaum, Modern Operating Systems, Prentice Hall PTR, Upper Saddle River, NJ, 2001
• 7: Alexander Thomasian , Chang Liu, Disk scheduling policies with lookahead, ACM SIGMETRICS Performance Evaluation Review, v.30 n.2, September 2002 [doi>10.1145/588160.588165]

INDEX TERMS

Primary Classification:
  K. Computing Milieux
  K.3 COMPUTERS AND EDUCATION
      K.3.2 Computer and Information Science Education
          Subjects: Computer science education

General Terms:
Human Factors, Languages

Keywords:
LBA, disk, disk scheduling, logical block addressing, scheduling, simulation controller