“I/O Optimization for Mobile Flash Storage”

Title: “I/O Optimization for Mobile Flash Storage”

Speaker: Prof. Chun Jason Xue, City University of Hong Kong

Date and Time: Tuesday, December 5, 2017 at 10:00AM-11:00AM

Location: DBH 3011


NAND flash memory is the primary choice of data storage for mobile devices due to its high performance, shock resistance and low power consumption. However, compared to high-end solid-state drives, mobile flash storage does not have the luxury of sophisticated hardware and firmware features because of the resource-constraint limits. Instead, mobile flash storage often equipped with scarce built-in RAM, slow embedded processors and low-cost flash memories, all of which make it a challenge to apply traditional techniques for I/O performance improvements. This talk presents a couple of work that we have done recently to optimize I/O for Mobile Flash Storage. First, this talk will introduce a novel I/O scheduling approach to improve demand-based page-level mapping cache performance. This technique generates mapping cache friendly I/O workloads by strengthening I/O locality at host I/O scheduler. Both temporal locality and spatial localities are taken into consideration for I/O scheduling. Second, this talk will present a lightweight data compression technique at the flash controller to reduce write pressure on mobile flash storage. It first characterizes data compressibility based on real smartphones, and the analysis shows that write traffics bound to mobile storage volumes are highly compressible. This technique is the first to investigate firmware-based data compression for mobile flash storage without adding extra data compression hardware. Experimental results demonstrate the proposed techniques outperform state-of-the-art schemes in terms of I/O latency and flash memory lifespan.


Dr. Chun Jason Xue is an Associate Professor at City University of Hong Kong Computer Science Department. His research interests include non-volatile memories, embedded and real time systems. He is currently Associate Editor for ACM Transaction on Embedded Computing Systems, Associate Editor for ACM Transaction on CPS, Associated Editor for ACM Transaction on Storage. He was the TPC co-chair for LCTES 2015, TPC co-char for ISVLSI 2016, and has served as TPC members in premiere conferences such as DAC, DATE, RTSS, RTAS, CODES, EMSOFT and ISLPED.