中文摘要：

在现代基于虚拟化的数据中心中，虚拟机分配是实现云中资源有效调度的首要考虑。已经证明对数据结点分配虚拟机并考虑虚拟机之间的通信延迟，使得最大通信延迟最小的问题是NP-hard问题。目前鲜有在数据中心网络虚拟机分配问题上考虑其安全性和可靠性的研究。针对虚拟机分配中的容错技术，提出了一种具有可控虚拟机冗余度的启发式分配算法。 算法以最大通信延迟最小化为优化目标，在可利用的虚拟机集合中通过构造可控冗余度的团来分配处理数据结点。实验结果表明，在Tree、VL2、Fat-tree和BCube四种常用的网络结构中，提出的启发式算法能提供0-200%之间任意冗余度。同时，在冗余度介于0~40%时，虚拟机与数据结点的匹配时间平均降低了67.1%，并且算法运行时间平均降低了12.8%。

英文摘要：

In modern data centers based on virtualization, virtual machine （VM） allocation is the primary consideration for efficient resources scheduling in the cloud. It has been proved that the VM allocation （VMA） problem to minimize the maximum access latency is of NP-hard. But few works on fault tolerant algorithms for the VMA problem are reported, which is very important for the security and reliability of the data center network. We present a heuristic algorithm focusing on minimizing the maximum data access latency. The proposed fault tolerant algorithm constructs the group with controllable redundancy in the set of available VMs, and then selects the VMs from the group and assigns them to the data nodes in the data center network. Extensive experiments on the Tree, VL2, Fat-Tree and BCube, the four commonly used network structures, show that the proposed algorithm can provide between 0 and 200% redundancy, the assignment time of virtual machines for the data nodes is reduced by 67.1% on average when redundancy is between 0 and 40%, and the running time of the algorithm is generally reduced by 12.8%.