In this paper, we investigate the effect ] of the prolonged service time at the non-dedicated servers in a pooling systemon the system performance. We consider the two-server loss model with exponential interarrival and service times. We show that if the ratio of the mean service time at the dedicated server and the mean prolonged service time at the non-dedicated server exceeds a certain threshold, pooling would become unfavourable. In particular, the threshold is explicitly provided. Moreover, when the degree of the prolonged service time is pre-specified, we show that the pooling system with prolonged service time at non-dedicated servers is not preferred when the work load in the systemis greater than a certain threshold .
The prolonged service time at non-dedicated servers has been observed in 1]. Motivated by such real problems, we propose a stylized model which characterizes the feature of the prolonged service time at non-dedicated servers in an asymmetric system. We study the independent system, the full flexibility system and the partial flexibility system when the occupation rate of the system, the degree of the prolonged service time and the degree of the asymmetry are allowed to change. We show that under certain circumstances, the partial flexibility scheme outperforms the full flexibility system and the independent system in such a model. Our results also provide instructions on how to introduce flexibility when the service time at non-dedicated servers is prolonged in an asymmetric system .
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In this paper, we investigate the effect
The prolonged service time at non-dedicated servers has been observed in
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1
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. Motivated by such real problems, we propose a stylized model which characterizes the feature
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the
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a pooling systemon the system performance. We consider the two-server loss model with exponential interarrival and service times. We show that if the ratio of the mean service time at the dedicated server and the mean prolonged service time at the non-dedicated server exceeds a certain threshold, pooling would become unfavourable. In particular, the threshold is explicitly provided. Moreover, when
an asymmetric system. We study the independent system, the full flexibility system and the partial flexibility system when the occupation rate of the system,
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is pre-specified, we show that the pooling system with prolonged
and the degree of the asymmetry are allowed to change. We show that under certain circumstances, the partial flexibility scheme outperforms the full flexibility system and the independent system in such a model. Our results also provide instructions on how to introduce flexibility when the
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not preferred when the work load in the systemis greater than a certain threshold
prolonged in an asymmetric system