Describing program behavior in a multiprogramming computer system
Joseph W. Keim, Herbert D. Schwetman · Annual Simulation Symposium · 1975
In order to simulate the behavior of a computing system some type of description of the behavior of jobs in that system needs to be specified. In this paper the behavior of batch jobs in a multiprogramming computer system is studied. A detailed trace of system and resource usage patterns over a time interval is collected using a software monitor embedded in the operating system. From this trace data the system and resource usage of each job encountered during that time interval can be obtained. A job is considered to consist of a sequence of steps with each step being invoked by a control card. We are then able to associate with each control card the behavior of the job during the time in which that control card is in force. One model of behavior is presented; this model describes a job step in terms of its CPU and system service routine requirements. Since many control cards invoke standard system programs (compilers, utilities, etc.) the typical behavior of these programs can be deduced. Data describing this behavior for various programs is presented in this paper. Application of such information to the simulation and evaluation of adaptive scheduling policies is mentioned.