基于预传输的虚拟机双机热备可用性研究

Research on Availability of Virtual Machine Hot Standby Based on Pre-transfer

针对虚拟机双机热备中传统拷贝技术导致的虚拟机低可用性问题,提出一种基于分段挑选最近未使用(SSNUR)算法的预传输方法。在虚拟机运行阶段预先传输被使用的内存页,减少停机阶段需要拷贝的内存页数量,使用SSNUR算法挑选预传输页面,以降低预传输和停机传输的重复率。实验结果表明,与XEN4.0中典型的虚拟机双机热备系统Remus相比,基于预传输的Remus系统在重负载和长间隔时间状态下停机时间明显减少,最高可达23.37%。

Apre transfer method based on Segment Selection Not Used Recently（SSNUR） algorithm is presented to solve low availability caused by the traditional copy technology in the virtual machine hot standby.The used memory pages are pre transferred in the running phase of the virtual machine,in order to reduce the number of memory pages to copy in the shutdown phase,and SSNUR algorithm is proposed to select the pages need to copy in order to reduce the repetition rate of pre transfer and stop transfer.Experimental results show that the pre transfer Remus compred with the original method has obvious advantages when the virtual machines have heavy load and long intervals,and downtime can be reduced up to 23.37%.