2878	 Joining Policies in a Multipriority Multiclass Batch Computer System	 Consider a multipriority batch computer system which users from several different classes may join its toll service and waiting charges. Such a system is formulated here as a semi-Markov decision process in which the aim of arriving users is to minimize their expected loss. The optimal joining policy is one of arriving users who may join the system at some of its queues is a control limit policy with a single control number for any possible queue and the user s class a newly arriving user will join a queue that is not filled up to the control number corresponding to this queue and the user s class. In this paper control numbers as well as lower and upper bounds for the control numbers and the capacities of the system s queues are derived. priority queues semi-Markov process price scheduling operating system
