103.
The MultiServer centre with Concurrent Classes of Customers (MSCCC) is a service centre consisting of
B parallel identical exponential servers. The customers requesting service at the MSCCC centre belong to
K groups. Customers arriving at the MSCCC centre are queued in the order of their arrival. A customer from group
k will go into service at the MSCCC centre provided that one or more of the
B servers is free and that at most
n − 1 other group
k customers are in service at the MSCCC centre.
The MSCCC centre can be applied to model systems where customers simultaneously occupy two resources. The system resources are partitioned into K primary and B secondary resources. A customer of group k can access primary resource k if it already is in possession of a secondary resource and if at most n − 1 other group k customers are using primary resource k.
This paper defines the MSCCC centre and presents several examples of computer (sub)systems that can be modelled using the MSCCC centre. The MSCCC centre is shown to satisfy local balance: therefore a multiclass queuing network consisting of BCMP and MSCCC centres has a product form solution. The joint probability distribution (JPD) for a queuing network consisting of several BCMP centres and one MSCCC centre is derived. Aggregation techniques are next used to reduce the JPD to a computationally tractable form. A Mean Value Analysis algorithm is presented for calculating the closed and open chain performance measures at the MSCCC centre. 相似文献