Towards Unified-storage-memory-enabled Mobile Devices

Description

Non-Volatile Memories (NVM) can serve as both the main memory and the storage, which makes it possible for a unified management of NVM for both storage and the main memory. While there are attempts to utilize unified-storage-memory to improve the performance of servers, unified-storage-memory has not been explored for mobile devices. We find that unified-storage-memory has potential to significantly improve the performance of mobile applications and improve the overall user experience. However, designing unified non-volatile memory management for mobile devices comes with significant challenges from three unique characteristics of mobile applications. First, a large percentage of read/write accesses on mobile devices are small in size. Under unified-storage-memory, the data movements between the main memory and the storage can be significantly reduced as they are on the same physical device. However, small-size data movement could induce significant overhead hence calls for new solutions. Second, mobile applications constantly perform sync operations to maintain data consistency in the case of power outages. These operations could benefit from the non-volatile main memory of the unified-storage-memory architecture and the application-transparent management of NVM. Third, mobile applications are user-experience- critical when they are in the foreground. Hence, the foreground applications should be prioritized under unified-storage-memory architecture by a carefully-designed memory/storage management scheme.  Considering the opportunities and challenges brought forward by these mobile application characteristics, this project proposes a novel unified-storage-memory framework for mobile devices. The proposed framework synergistically combines unified-storage-memory’s features and mobile applications’ characteristics to improve the user experience and performance of mobile devices. First, we profile mobile application execution on unified-storage-memory. Foreground/background aware memory management schemes, as well as dynamic memory/storage management schemes will be exploited to improve performance and reduce power consumption for mobile devices. Second, targeting efficient application execution on unified-storage-memory, we explore persistent application execution on unified-storage-memory and granularity-aware application launching over unified memory. Finally, we propose application-aware I/O schemes for unified-storage-memory, considering the specific characteristics of mobile devices, including mobile cache file management and data-intensive- device management.   Unified-storage-memory could play an increasingly important role for mobile devices in the upcoming decade. The success of this project will promote the application of the new architecture of mobile devices. High performance, low power consumption, and long device’s lifespan can benefit many mobile users. The success is highly critical for Hong Kong to drive its new wave of innovation and technology in the mobile computing era.