Real-time system with homogeneous servers and nonidentical channels in steady-state

Abstract

A real-time multiserver system with homogeneous servers (such as unmanned air vehicles or machine controllers) and several nonidentical channels (such as surveillance regions or assembly lines) working under maximum load regime is studied. We show how to compute steady-state probabilities of such a system, when both maintenance and service times are exponentially distributed. We also compute various important performance parameters, including system availability and loss penalty function. Scope and purpose Real-time systems are responsible for operations management of increasingly sensitive applications, particularly those in which failures to satisfy timing constraints can lead to serious or even catastrophic consequences. In these systems, a job is processed immediately upon arrival (conditional on system availability) without delay. That part of the job which is not executed immediately is lost and cannot be served later. It has become more important to use the analytical methodologies to ensure that the designs and implementations of time-dependent systems are verifiably correct and predictable. This paper shows how to use the methods of stochastic processes and queueing theory in the analysis of multiserver real-time system with different channels, where queueing of jobs is impossible. Failures of some (or even majority) of system components lead only to gradual degradation of the system ability to perform its functions. In the paper this ability is presented by system availability and loss penalty function.