Exploiting Free Silicon for Energy-Efficient Computing Directly in NAND Flash-based Solid-State Storage Systems Peng Li Kevin Gomez David J. Lilja Seagate Technology Seagate Technology University of Minnesota, Twin Cities Shakopee, MN, 55379 Shakopee, MN, 55379 Minneapolis, MN, 55455
[email protected] [email protected] [email protected] Abstract—Energy consumption is a fundamental issue in today’s data A well-known solution to the memory wall issue is moving centers as data continue growing dramatically. How to process these computing closer to the data. For example, Gokhale et al [2] data in an energy-efficient way becomes more and more important. proposed a processor-in-memory (PIM) chip by adding a processor Prior work had proposed several methods to build an energy-efficient system. The basic idea is to attack the memory wall issue (i.e., the into the main memory for computing. Riedel et al [9] proposed performance gap between CPUs and main memory) by moving com- an active disk by using the processor inside the hard disk drive puting closer to the data. However, these methods have not been widely (HDD) for computing. With the evolution of other non-volatile adopted due to high cost and limited performance improvements. In memories (NVMs), such as phase-change memory (PCM) and spin- this paper, we propose the storage processing unit (SPU) which adds computing power into NAND flash memories at standard solid-state transfer torque (STT)-RAM, researchers also proposed to use these drive (SSD) cost. By pre-processing the data using the SPU, the data NVMs as the main memory for data-intensive applications [10] to that needs to be transferred to host CPUs for further processing improve the system energy-efficiency.