This project is a study of the processor scheduling system in UNIX 4.2BSD. This study involved a computer simulation of the processor scheduling system. The preliminary work for the simulation included choosing a system, choosing and running a set of test processes on that system, gathering statistics from these runs, and constructing a model of the scheduling system. The model was then tuned to perform like the real system by introducing overhead into the model. The overhead was added using several variables in the model. Tuning consisted of adjusting the values of these variables until the performance of the model was as close as possible to that of the real system. Experiments were performed on the model consisting of a rescheduling experiment that examined the handling of compute-bound processes by the scheduler and several experiments that study the effects of modifications to the scheduler.

Library of Congress Subject Headings

UNIX (Computer file); Operating systems (Computers)--Data processing--Simulation methods; Computer simulation

Publication Date


Document Type


Department, Program, or Center

Computer Science (GCCIS)


Carbin, James

Advisor/Committee Member

Carithers, Warren

Advisor/Committee Member

Kitchen, Andrew


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: QA76.8.U65 G765 1987


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