Class Pfqn_mwrbb
Computes distribution-insensitive (NBUE) upper and lower bounds on the per-class system throughput of a closed multiclass queueing network, per S. Majumdar and C.M. Woodside, "Robust bounds and throughput guarantees for closed multiclass queueing networks", Performance Evaluation 32 (1998) 101-136. The upper bound intersects the no-contention bound (eq. 2) with the utilization-based bound (eq. 3) and is independent of the scheduling discipline. The lower bound is the multiclass throughput guarantee of Theorem 2 (eq. 15): X_c >= N_c / (Z_c + sum_k V_kc (S_kc + d_kc+)), where the per-visit queueing delay bound d_kc+ depends on the discipline at station k -- FIFO (Theorem 1 / eq. 6, via Lemma 1), processor sharing (Lemma 2), preemptive priority (Lemma 3) and non-preemptive priority (Lemmas 4-5). The coupled inequalities are resolved by the interval- narrowing fixed point reproducing the BNR-Prolog robust box bounds; for a single FIFO class it reduces to the Muntz-Wong asymptotic bounds.
Bounds are insensitive to the service-time distributions (only NBUE is assumed) and to routing dependencies. The think time Z aggregates the pure-delay (infinite-server) stations; only queueing stations are passed in V,S.
- Since:
- LINE 3.0
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Nested Class Summary
Nested ClassesModifier and TypeClassDescriptionstatic final class -
Field Summary
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Method Summary
Modifier and TypeMethodDescriptionstatic Pfqn_mwrbb.Resultpfqn_mwrbb(Matrix V, Matrix S, Matrix N, Matrix Z) FIFO, equal-priority convenience overload.static Pfqn_mwrbb.Result
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Field Details
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FIFO
public static final int FIFODiscipline codes for theschedargument.- See Also:
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PS
public static final int PS- See Also:
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NPPRIO
public static final int NPPRIO- See Also:
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PPPRIO
public static final int PPPRIO- See Also:
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ABA
public static final int ABA- See Also:
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Method Details
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pfqn_mwrbb
FIFO, equal-priority convenience overload. -
pfqn_mwrbb
public static Pfqn_mwrbb.Result pfqn_mwrbb(Matrix V, Matrix S, Matrix N, Matrix Z, Matrix sched, Matrix prio) - Parameters:
V- (K x C) mean visits of class c at queueing station kS- (K x C) mean service demand per visit of class c at station kN- (1 x C) or (C x 1) population of class cZ- (1 x C) or (C x 1) think time of class c (may be null)sched- (K x 1) discipline code per station (0=FIFO, 1=PS, 2=non-preemptive priority, 3=preemptive priority); null => all FIFOprio- (1 x C) class priority, lower value = higher priority; null => all equal- Returns:
- robust box bounds and per-visit residence times
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