Memory disaggregation: why now and what are the challenges.

Hardware disaggregation has emerged as one of the most fundamental shifts in how we build computer systems over the past decades. While disaggregation has been successful for several types of resources (storage, power, and others), memory disaggregation has yet to happen. We make the case that the time for memory disaggregation has arrived. We look at past successful disaggregation stories and learn that their success depended on two requirements: addressing a burning issue and being technically feasible. We examine memory disaggregation through this lens and find that both requirements are finally met. Once available, memory disaggregation will require software support to be used effectively. We discuss some of the challenges of designing an operating system that can utilize disaggregated memory for itself and its applications.