虛擬化 ARM 平台上的 μCOS-III 移植實作

Abstract

Mobile devices have become indispensable to our lives; the functionality of operating systems (OSes) and applications on mobile devices keeps growing dramatically and diversely. As the progressive capability of embedded processors, people start thinking of the feasibility of adopting virtualization technology in mobile devices. Virtualization allows multiple OSes executing on the same machine simultaneously. This not only increases the utilization of system resources but also breaks the boundaries between OSes and enables efficient and seamless integration of cloud computing. However, research on mobile virtualization is still at the very early stage. Especially, for large distributed applications involving mobile device, personal computer and cloud server, it is very difficult to fulfill features like task migration because the interfaces of these OSes might not be compatible. Therefore, we propose to adopt virtual platforms to emulate the mobile devices on personal computer with the same OS run on physical device, so that there could be a general interface among OSes on different hardware architectures for easier task migration. μC/OS is a popular lightweight embedded OS for verifying the feasibility of this idea. In this thesis, we port μC/OS from physical machine to virtualized ARM machine on personal computer. In order to reduce the overhead of virtualization, we design a history-based optimization mechanism to speed up the emulation of virtual machines running the same OS. The experiment results show that the performance of CPU-bound workloads can speed up to 21%. In the trend of virtualizing mobile devices, we believe our implementation result of the optimized virtualization platform is perspective and practical for many large distributed applications.