Higher Moment Approximation of Fork / Join
نویسندگان
چکیده
In this paper we present an approximate analysis of fork/join prim-itives with two parallel servers, limited buuers and non-zero join times where either jobs arrive according to a Poisson process (open system) or the number of jobs is limited according to the CONWIP rule (closed system). The approximation method is based on the concept of ow-equivalent servers and enables the approximate analysis of higher moments of the cycle time. We extend the concept of ow-equivalent servers and replace the two-processor fork/join primitive by a queuing network consisting of two single servers in tandem where one of them has state-dependent service rates. The comparison of approximate to exact results for both the mean and the variance of response times shows that our method works very accurate for a large range of parameter settings.
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