Queueing systems with server vacations (server’s performing non-queueing jobs) have been studied extensively since the late 70’s. A considerable number of works in this area were completed in the early 80’s and surveyed by Doshi in 1986. As an extension to the classical queueing system, allowing idle servers to work on non-queueing jobs makes the vacation models more applicable in a variety of ...

In this paper we study message flow processes in distributed simulators of open queueing networks. We develop and study queueing models for distributed simulators with maximum lookahead sequencing. We characterize the “external” arrival process, and the message feedback process in the simulator of a simple queueing network with feedback. We show that a certain “natural” modelling construct for ...

Within the scheduling community, there has recently been an increasing interest in modelling and solving of scheduling problems in dynamic and uncertain environments. Such research does not utilize the developments of queueing theory, an area that has examined problems of similar nature. This paper is initial work towards the goal of integrating queueing theory and scheduling. Specifically, by ...

Controlling the timing performance of a network server is a challenging problem. This paper presents a Queueing Model Based Feedback Control approach to keep the timing performance of a network server close to the service level specification. We show that in an instrumented Apache server, combining feedback control with a queueing model leads to better tracking of QoS specifications than with f...

The modern queueing theory is one of the powerful tools for a quantitative and qualitative analysis of communication systems, computer networks, transportation systems, and many other technical systems. The paper is designated to the analysis of queueing systems, arising in the networks theory and communications theory (called open queueing network). The authors of this research in the sphere o...

this paper analyzes an m/m/2 queueing system with two heterogeneous servers. both servers goes on vacation when there is no customers waiting for service after this server 1 is always available but the other goes on vacation whenever server 2 is idle. the vacationing server however, returns to serve at a low rate as an arrival finds the other server busy. the system is analyzed in the steady st...

We introduce queueing network models for characterizing and modeling the performance of graph programs. We show that graph programs can be modelled as a queuing network whose behaviour can be mapped to a queueing network of the underlying architecture. Operational analysis of these queueing networks allows us to systematically analyze performance and identify performance bottlenecks. We demonst...

With the increasing popularity and diversity of computer systems, quality of services for computer applications becomes more and more important. In order to facilitate the theoretical studies on the computer performance management problem, an effective simulation environment is desired. In this paper, we propose a methodology of extracting a queueing model from the measurements of computer syst...

Controlling the timing performance of a network server is a challenging problem. This paper presents a Queueing Model Based Feedback Control approach to keep the timing performance of a network server close to the service level specification. We show that in an instrumented Apache server, combining feedback control with a queueing model leads to better tracking of QoS specifications than with f...

Conventional analysis techniques of queueing systems typically assume that the stochastic process under study is already in steady state. This assumption is, however, not valid if the life cycle of the process is not large enough. Previous work in transient analysis of queueing systems usually focuses on Markov models. This paper, in contrast, presents an analysis technique for investigating tr...