Energy-aware demand paging on NAND flash-based embedded storages

The ever-increasing requirement for high-performance and huge-capacity memories of emerging embedded applications has led to the widespread adoption of SDRAM and NAND flash memory as main and secondary memories, respectively. In particular, the use of energy consuming memory, SDRAM, has become burdensome in battery-powered embedded systems. Intuitively, though demand paging can be used to mitigate the increasing requirement of main memory size, its applicability should be deliberately elaborated since NAND flash memory has asymmetric operation characteristics in terms of performance and energy consumption. In this paper, we present an energy-aware demand paging technique to lower the energy consumption of embedded systems considering the characteristics of interactive embedded applications with large memory footprints. We also propose a flash memory-aware page replacement policy that can reduce the number of write and erase operations in NAND flash memory. With real-life workloads, we show the system-wide energy-delay product can be reduced by 15∼30% compared to the traditional shadowing architecture.