Virtual Machine Image Content Aware I/O Optimization for Mobile Virtualization

Mobile virtualization introduces extra layers in software stacks, which leads to performance degradation. Especially, each I/O operation has to pass through several software layers to reach the NAND-flash-based storage systems. This paper targets at optimizing I/O for mobile virtualization, since I/O becomes one of major performance bottlenecks that seriously affects the performance of mobile devices. Among all the I/O operations, a large percentage is updating metadata. Frequent updating metadata not only degrades overall I/O performance but also severely reduces flash memory lifetime. In this paper, we propose a novel I/O optimization techniqueto identify the metadata of a guest file system which is storedin a VM (Virtual Machine) image file and frequently updated. Then, these metadata are stored in a small additional NVM(Non-Volatile Memory) which is faster and more endurableto greatly improve flash memory´s performance and lifetime. To the best of our knowledge, this is the first work to identifythe file system metadata from regular data in a guest OS VMimage file under mobile virtualization. The proposed schemeis evaluated on a real hardware embedded platform. Theexperimental results show that the proposed techniques canimprove write performance to 45.21% in mobile devices withvirtualization.