Power series approximations for two-class generalized processor sharing systems

We develop power series approximations for a discrete-time queueing system with two parallel queues and one processor. If both queues are nonempty, a customer of queue 1 is served with probability β, and a customer of queue 2 is served with probability 1−β. If one of the queues is empty, a customer of the other queue is served with probability 1. We first describe the generating function U(z1,z2) of the stationary queue lengths in terms of a functional equation, and show how to solve this using the theory of boundary value problems. Then, we propose to use the same functional equation to obtain a power series for U(z1,z2) in β. The first coefficient of this power series corresponds to the priority case β=0, which allows for an explicit solution. All higher coefficients are expressed in terms of the priority case. Accurate approximations for the mean stationary queue lengths are obtained from combining truncated power series and Padé approximation.

[1]  J. Kingman Two Similar Queues in Parallel , 1961 .

[2]  Gerard Hooghiemstra,et al.  The M/G/1 processor sharing queue as the almost sure limit of feedback queues , 1990 .

[3]  Herwig Bruneel,et al.  Performance analysis of a GI-Geo-1 buffer with a preemptive resume priority scheduling discipline , 2004, Eur. J. Oper. Res..

[4]  G. Fayolle,et al.  Random Walks in the Quarter-Plane: Algebraic Methods, Boundary Value Problems and Applications , 1999 .

[5]  Andreas Brandt,et al.  On the sojourn times for many-queue head-of-the-line Processor-sharing systems with permanent customers , 1998, Math. Methods Oper. Res..

[6]  J. W. Cohen,et al.  Boundary value problems in queueing theory , 1988, Queueing Syst. Theory Appl..

[7]  Alan Scheller-Wolf,et al.  Analysis of cycle stealing with switching times and thresholds , 2005, Perform. Evaluation.

[8]  Gerard Hooghiemstra,et al.  Power series for stationary distributions of coupled processor models , 1988 .

[9]  J. Wessels,et al.  A COMPENSATION APPROACH FOR TWO-DIMENSIONAL , 1993 .

[10]  I. N. Sneddon,et al.  Boundary value problems , 2007 .

[11]  Andreas Brandt,et al.  A note on the stability of the many-queue head-of-the-line processor-sharing system with permanent customers , 1999, Queueing Syst. Theory Appl..

[12]  Herwig Bruneel,et al.  Delay characteristics in discrete-time GI-G-1 queues with non-preemptive priority queueing discipline , 2002, Perform. Evaluation.

[13]  Harold R. Parks,et al.  The Implicit Function Theorem , 2002 .

[14]  Fabrice Guillemin,et al.  Analysis of generalized processor-sharing systems with two classes of customers and exponential services , 2004, Journal of Applied Probability.

[15]  J. Dieudonne Foundations of Modern Analysis , 1969 .

[16]  A. W. Kemp,et al.  Applied Probability and Queues , 1989 .

[17]  J. P. C. Blanc,et al.  A Numerical Study of a Coupled Processor Model , 1987, Computer Performance and Reliability.

[18]  Onno Boxma,et al.  Boundary value problems in queueing system analysis , 1983 .

[19]  Johan van Leeuwaarden,et al.  On the application of Rouché's theorem in queueing theory , 2006, Oper. Res. Lett..

[20]  G. Fayolle,et al.  Two coupled processors: The reduction to a Riemann-Hilbert problem , 1979 .

[21]  S. Asmussen,et al.  Applied Probability and Queues , 1989 .

[22]  Ivan Atencia,et al.  A discrete-time Geo[X]/G/1 retrial queue with control of admission , 2005 .

[23]  J. Blanc On a numerical method for calculating state probabilities for queueing systems with more than one waiting line , 1987 .

[24]  W. B. van den Hout,et al.  The power-series algorithm. A numerical approach to Markov processes , 1996 .

[25]  A. Konheim,et al.  Processor-sharing of two parallel lines , 1981, Journal of Applied Probability.

[26]  Ivo J. B. F. Adan,et al.  Queueing Models with Multiple Waiting Lines , 2001, Queueing Syst. Theory Appl..