近年來虛擬化技術可說是最熱門的關鍵字，虛擬化技術允許同一台實體機器上能同時運行多個虛擬機器，這些虛擬機器擁有各自的作業系統，且這些位於相同實體主機上的虛擬機器是彼此獨立，就如同擁有實體環境一樣，而虛擬化技術運行至今，已經有多數的企業導入，虛擬化技術提供了方便管理、有效地利用資源、省電…等優點，透過虛擬化技術使用者可以動態的調整虛擬機器所擁有的資源(CPU,Memory…)，而I/O部分卻只能透過搬移來達到調整的效果，所以我們在虛擬機器的環境上提出了一個混合式儲存系統的存取架構，利用少量的固態硬碟空間來達到提升整體I/O速度的功能。

Server virtualization is a technology for partitioning one physical machine into multiple virtual machines. Each of these virtual machines can run its own operating system and applications, and perform as if it is an individual machine. Nowadays server virtualization technology has been widely used in the data center and services computing area. Server virtualization technology can greatly improve server utilization, simplify server management and maintenance and reduce costs. The required resources for each individual virtual machine can be adjusted dynamically and easily. However, due to the hardware limitation of storage device, virtual machine has no ability to improve I/O performance .So we propose a hybrid storage access framework for machine, it can improve I/O performance by using solid-state drive.

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