MLP aware heterogeneous memory system

Main memory plays a critical role in a computer system´s performance and energy efficiency. Three key parameters define a main memory system´s efficiency: latency, bandwidth, and power. Current memory systems tries to balance all these three parameters to achieve reasonable efficiency for most programs. However, in a multi-core system, applications with various memory demands are simultaneously executed. This paper proposes a heterogeneous main memory with three different memory modules, where each module is heavily optimized for one the three parameters at the cost of compromising the other two. Based on the memory access characteristics of an application, the operating system allocates its pages in a memory module that satisfies its memory requirements. When compared to a homogeneous memory system, we demonstrate through cycle-accurate simulations that our design results in about 13.5% increase in system performance and a 20% improvement in memory power.