多虚拟机环境下磁盘写优化机制

在虚拟化环境下,如何在写直达法和写回法之间做出权衡以使系统既具有较好的可靠性又具有较高的磁盘读写性能,是一个亟待解决的问题。本文提出了基于XEN的兼有写直达法和写回法优点的磁盘数据写操作方法。通过修改虚拟机块设备前后端驱动程序,在虚拟机管理器中为每个虚拟机建立块级别的虚拟机磁盘缓存。虚拟机中的应用程序均采取写直达的方式,将数据直接写到位于虚拟机管理器的虚拟机磁盘缓存中。结果表明,该机制能为虚拟机提供高效率的磁盘读写操作,同时,在虚拟机系统突然宕机时也能保证用户数据的完整性和可靠性。

Optimization Scheme of Disk Write in Multiple Virtual Machines

In virtualization environment,how to develop a novel data transfer method,which not only ensures the stability but also guarantees the performance of the system based on write-through and write-back schemes,is an attractive topic.Based on the platform of computing system virtualization XEN,this paper proposes a new scheme to deal with dirty memory data effectively and reliably with the help of virtualized environment.This method is equipped with the advantages of both write-through and write-back method in traditional architectures.It not only ensures the integrity and reliability of user data in the situation of system crash,but also provides satisfying performance with applications.Experiments are carried out to evaluate the system.The results show that the new scheme is able to work efficiently and can well protect the integrity of user data even if the operating system crashes unexpectedly.