NVMRA: utilizing NVM to improve the random write operations for NAND-flash-based mobile devices

NAND flash memory has become the major storage media in mobile devices, such as smartphones. However, the random write operations of NAND flash memory heavily affect the I/O performance, thus seriously degrading the application performance in mobile devices. The main reason for slow random write operations is the out-of-place update feature of NAND flash memory. Newly emerged non-volatile memory, such as phase-change memory, spin transfer torque, supports in-place updates and presents much better I/O performance than that of flash memory. All these good features make non-volatile memory (NVM) as a promising solution to improve the random write performance for NAND flash memory. In this paper, we propose a non-volatile memory for random access (NVMRA) scheme to utilize NVM to improve the I/O performance in mobile devices. NVMRA exploits the I/O behaviors of applications to improve the random write performance for each application. Based on different I/O behaviors, such as random write-dominant I/O behavior, NVMRA adopts different storing decisions. The scheme is evaluated on a real Android 4.2 platform. The experimental results show that the proposed scheme can effectively improve the I/O performance and reduce the I/O energy consumption for mobile devices.