得利於雲端計算相關研究與虛擬化技術兩者的快速發展，資訊產業可以使用相關技術將複數個伺服器整合到同一實體機器上，同時可以有更彈性的資源分配以及更高的利用效率。然而，實體機器因為硬體或者人為因素導致故障造成在其上運行的服務失效問題也隨之而來；基於虛擬化技術的容錯系統可以在實體機器因為某些因素發生故障時，保護其關鍵服務之虛擬機狀態，提升系統的可用(靠)性。
本研究基於QEMU 3.0.0與持續同步架構做出可透過外部管理介面控制的容錯系統；持續同步架構透過不斷將主要虛擬機器上的虛擬機狀態，同步到備援虛擬機狀態上，並基於容錯系統基本要求，保持兩者對外輸出的一致性。同時本研究引入管線化來改善因同步造成的成本，並且提升虛擬機效能、在兩次同步之間投機式的傳送虛擬機狀態，使得在同步時的時間成本減少，減少反應時間。

Benefiting from the rapid development of both cloud computing-related research and virtualization technology, the IT industry can use related technologies to integrate multiple servers on the same physical machine, and at the same time. It can have more flexible resource allocation and higher utilization efficiency. However, because of hardware or human factors causes the services which running on the physical machine failure or cannot provide services. A fault-tolerant system based on virtualization technology can protect its important services when the physical machine fails due to some factors, and improve the availability or reliability of the system.
This research is based on QEMU 3.0.0 and the continuous checkpointing architecture to implement a fault-tolerant system that can be controlled through an external management interface. The continuous checkpointing architecture continuously synchronizes the state of the virtual machine on the main virtual machine to the state of the backup virtual machine, and is based on fault tolerance the basic requirements of the system are to maintain the consistency of the external output of the two. At the same time, this research introduces pipeline method to improve the cost caused by synchronization, and improve the performance of the virtual machine, and speculatively transfer the virtual machine state between two checkpointing, so that the time cost during synchronization is reduced and the response time is reduced.

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