With New Memories Come New Challenges

The performance of a modern computer system is increasingly getting dictated by the performance of the memory system. As we pack more cores, more threads per core, and domain-specific accelerators on the chip, the memory system must scale in both capacity and bandwidth to supply the data to all these computing units. For the past four decades, we have had mainly two technologies for building the components of the memory system: SRAM for caches and DRAM for main memories, and systems have been limited by the constraints of these two technologies. It is argued that we are at a juncture where several new memory technologies are emerging that can overcome the limitations of conventional technologies and offer new features such as nonvolatility. However, with new technologies come new challenges and system designers will need innovative solutions to address these challenges in order to fully realize the benefits offered by the emerging technologies.