虚拟机管理器中面向虚拟块设备的一种通用快照扩展机制

基于虚拟机环境下虚拟块设备多样性的特点以及对高可用、容错等能力的需求,本文针对目前主流的虚拟机体系结构,提出了一种在虚拟机管理器中为虚拟块设备扩展通用快照功能的机制,能够为虚拟机环境下的多种虚拟块设备提供统一和可扩展的快照服务,有效避免了大幅修改底层的多种具体的虚拟块设备驱动。基于Linux平台,为QEMU扩展了通用的快照功能,验证了快照扩展机制的可行性,并通过实验测试分析了快照对虚拟机性能的影响。

A Mechanism of Extending the Generic Snapshot Capability for the Virtual Block Devices in Virtual Machine Monitors

Based on the characteristics of diversity of virtual block devices and requirements for the capabilities of high availability and fault tolerance,we propose a mechanism of extending the generic snapshot capability for the virtual block devices(VBD) in virtual machine monitors for the mainstream virtual machine(VM) architectures.Based on the mechanism,we can provide uniform and extensible snapshot services for the multiple VBDs in the VM environments while avoiding taking much efforts in modifying the low-level multiple specific VBD drivers.Based on a Linux system,we have extended the generic snapshot capability for QEMU to prove the feasibility of the extending mechanism,and have measured and analyzed the effects that snapshot brings to the VM performance through our experiments.