关键词: 云计算, 能耗, 威布尔分布, 形状参数, 半马尔科夫过程

Abstract: In the cloud computing environment, due to complex state of virtual machine normal operation, a novel method, processor running state is thought as hardware/software series repairable system and normal operation is described by Weibull distribution, is proposed to remit serious energy problems. The correlation model among processor utilization, energy and given task completion time is structured by a semi-Markov process which formulated for virtual machine operation, Laplace-Stielties transform which used to simplify numerical calculation, and Bayesian theorem which used to remove restricted condition. Combined with repairable system lifetime distribution theory, probability density function of VMs normal operation is changed. It can obtain processor operation energy consumption and a given task completion time under different shape parameter of Weibull distribution. The implied relationship among shape parameter, processor utilization, energy and performance is analyzed to give some rational proposal in order to effectively reduce energy consumption. Numerical examples results show that increasing shape parameter is superior to improving processor utilization about reducing energy consumption. Increasing shape parameter by improving processor configuration not only can significantly reduce energy consumption, and can avoid depletion of system performance.

Key words: cloud computing, energy consumption, Weibull distribution, shape parameter, semi-Markov process