For many decades, dynamic random access memory, or DRAM, has been the technology of choice for use as core processor memory storage. Although the functionality and general access characteristics of DRAM have not changed dramatically since its inception, the technology has evolved by continually improving in overall bit density. However, the success of DRAM has also enabled the emergence of the processor-memory latency gap. Much effort has been spent improving processor functionality and redesigning memory hierarchies to limit the effects of this growing gap in performance. In recent years, there has been a rapid onset of different designs proposed to attack the problem at the memory itself.
A summary of current DRAM and SRAM technologies focused on this problem is given, enumerating the specific design characteristics that differ among the proposals. Next, we present two technologies, intelligent RAM and magnetic RAM, which provide a fundamentally different perspective from conventional DRAM architectures for bridging the processor-memory gap. Our study is concluded by a discussion on the future of memory architectures.

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