Abstract: The existing dynamic consolidation of virtual machines algorithm which aims to reduce energy consumption does not consider the cost of the migration of virtual machines. Some migration of virtual machine is unreasonable, which probably increases the SLA（Service Level Agreements） violation. The results in dynamic consolidation of virtual machine decrease the energy consumption of data center. To address this problem, this paper proposes a migration cost-aware dynamic consolidation of virtual machine algorithm called MigCAP（Migration Cost Aware Policy）. It defines the migration profile parameter EMP and through this parameter, MigCAP chooses to migrate the virtual machines or not. The experimental results show that MigCAP method reduces not only energy consumption and SLA violation but also the number of migrations of virtual machines.

Key words: cloud computing, dynamic consolidation of virtual machines, power-aware, Service Level Agreements（SLA）, migration cost-aware

摘要： 现有的以降低能耗为目标的虚拟机动态整合算法通常忽略了虚拟机迁移所带来的消极影响，导致虚拟机的动态整合虽然减少了数据中心的能耗，但不合理的虚拟机迁移次数较多，极有可能增加了SLA（Service Level Agreements）的违例率。针对上述问题，提出了一种迁移开销感知的虚拟机动态整合算法MigCAP（Migration Cost Aware Policy），定义了迁移收益参数EMP，MigCAP算法通过EMP值的大小来决定是否需要进行虚拟机的迁移，避免了不合理的虚拟机迁移的发生。实验结果表明，MigCAP算法与现有的其他虚拟机动态整合算法相比，能够在有效减少能耗和降低SLA违例率的基础上，显著减少虚拟机迁移次数。

关键词: 云计算, 虚拟机动态整合, 能耗感知, 服务等级协议（SLA）, 迁移开销感知