Optimization of Multiclass Queueing Networks with Changeover Times Via the Achievable Region Approach: Part II, The Multi-Station Case
研究了多站点多类排队网络在服务器切换时间下的调度问题,通过数学规划方法给出成本下界和启发式调度策略,帮助降低库存持有成本。
We address the problem of scheduling a multi-station multiclass queueing network (MQNET) with server changeover times to minimize steady-state mean job holding costs. We present new lower bounds on the best achievable cost that emerge as the values of mathematical programming problems (linear, semidefinite, and convex) over relaxed formulations of the system's achievable performance region. The constraints on achievable performance defining these formulations are obtained by formulating system's equilibrium relations. Our contributions include: (1) a flow conservation interpretation and closed formulae for the constraints previously derived by the potential function method; (2) new work decomposition laws for MQNETs; (3) new constraints (linear, convex, and semidefinite) on the performance region of first and second moments of queue lengths for MQNETs; (4) a fast bound for a MQNET with N customer classes computed in N steps; (5) two heuristic scheduling policies: a priority-index policy, and a policy extracted from the solution of a linear programming relaxation.