Reducing the “Tax” of Reliability: A Hardware-Aware Method for Agile Data Persistence in Mobile Devices

摘要

Nowadays, mobile devices are pervasively used by almost everyone. The majority of mobile devices use embedded-Multi Media Cards (eMMC) as storage. However, the crash-proof mechanism of existing I/O stack has not fully exploited the features of eMMC. In some real usage scenarios, the legacy data persistence procedure may dramatically degrade performance of the system. In response to this, this paper exploits the hardware features of eMMC to improve the efficiency of data persistence while preserving the reliability of current mobile systems. We characterize the existing data persistence scheme and observe that the hardware-agnostic design generates excessive non-critical data and adds expensive barriers in data persistence paths. We alleviate these overheads by leveraging eMMC features. Based on evaluations on real systems, our optimizations achieve 5%-31% performance improvement across a wide range of mobile apps.