FlashGPU: Placing New Flash Next to GPU Cores

Abstract

We propose FlashGPU, a new GPU architecture that tightly blends new flash (Z-NAND) with massive GPU cores. Specifically, we replace global memory with Z-NAND that exhibits ultra-low latency. We also architect a flash core to manage request dispatches and address translations underneath L2 cache banks of GPU cores. While Z-NAND is a hundred times faster than conventional 3D-stacked flash, its latency is still longer than DRAM. To address this shortcoming, we propose a dynamic page-placement and buffer manager in Z-NAND subsystems by being aware of bulk and parallel memory access characteristics of GPU applications, thereby offering high-throughput and low-energy consumption behaviors.