A simple analytic queueing model of software resource sharing in a multiprogramming
environment is presented. Implicit algebraic equations for steady state mean waiting times at
the various queues are developed. These equations may be solved by simple fixed point
iteration. It is shown that a solution always exists and that under non-restrictive conditions
the simple iteration does converge. An easily applied test for uniqueness of solution is given.
Tables of results and comparison with simulation solutions are included.