The energy consumption of virtualized data centers has grown very fast in last several years. Because a large number of hosts are running in an idle state, virtualized data centers waste a large amount of electric energy. To save more energy for virtualized data centers, an energy-saving mechanism is proposed based on switching operating mode of physical servers and reserving virtual machines (VMs). The main idea is that when the amount of idle VMs reaches twice of a specified threshold, half of these idle VMs are reserved to process the new task that is about to arrive, and the physical server which hosts the other half of the idle VMs is switched to the sleep mode. From the perspective of task arrival rate and sleep parameters, we use two-dimensional Markov processes to analyze the proposed energy-saving mechanisms. By using matrix geometry solutions, we theoretically estimate energy consumption and response performance. According to the numerical experiments, the proposed energy-saving mechanism obviously cut down electric energy consumption and ensures response performance. Finally, the specified threshold for the amount of VMs is optimized by building a cost function.

中文翻译：

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基于物理服务器运行模式切换和虚拟机预留的虚拟化数据中心节能机制

虚拟化数据中心的能源消耗在过去几年中增长得非常快。由于大量主机处于空闲状态，虚拟化数据中心浪费了大量电能。为了给虚拟化数据中心节省更多的能源，提出了一种基于切换物理服务器运行模式和预留虚拟机（VM）的节能机制。主要思想是当空闲虚拟机数量达到指定阈值的两倍时，保留这些空闲虚拟机的一半来处理即将到来的新任务，而托管另一半空闲虚拟机的物理服务器是切换到睡眠模式。从任务到达率和睡眠参数的角度，我们使用二维马尔可夫过程来分析提出的节能机制。通过使用矩阵几何解决方案，我们在理论上估计了能耗和响应性能。数值实验表明，所提出的节能机制明显降低了电能消耗，保证了响应性能。最后，通过构建成本函数来优化 VM 数量的指定阈值。