Comparison of single and double channel I/O-configurations
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This paper is concerned with the performance evaluation of I/O-configurations composed of channels and I/0 devices (magnetic disk, drum ...).
The question to be answered is: what performance improvement can be expected when the number of channels is increased or when the I/0-devices are multiple-ported instead of single-ported? To that end Markov chain models are developed for three different I/0-configurations. These models are analyzed under the assumption that a stochastic equilibrium is reached, and the probability generating function of the system occupancy is derived. From this function important performance measures, such as throughput and mean system occupancy are obtained as explicit functions of the system parameters. A quantitative comparison between the three alternatives is made.
KeywordsGenerate Function Markov Chain Performance Evaluation System Parameter Performance Improvement
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