【摘要】 相变内存是一种新兴的存储技术.相对于动态随机访问内存,相变内存具有高可扩展性和低功耗等特点,因此被认为是最有潜力的下一代存储技术.相变内存面临的挑战之一是其存储单元只能经受有限次写操作.因此,如何提高相变内存的耐久性成为亟待解决的问题.提出了一种基于代数映射的相变内存矩阵磨损均衡方法.该方法在每一列和每一行分别进行磨损均衡.通过从行和列两个维度进行两级地址映射,任意逻辑块都可以既在某个列地址空间中进行地址重映射,而被映射到任意一个行中;同时又可以在某个行地址空间中进行地址重映射,而被映射到任意一个列中.设计并实现了一个仿真系统来验证该方法,并进行了详细的功能正确性和抗攻击性能测试.矩阵磨损均衡有效地实现了相变内存抗不均衡写访问、抗恶意写攻击和降低磨损均衡引起的额外写访问开销等目标.更多还原

【Abstract】 Phase-change memory (PCM) is an emerging memory technique. PCM offers many advantages over traditional DRAM, and thus has the potential to be the next generation main memory in computer systems. One of the hurdles for its use is the limited number of writes to storage cells. Furthermore, the non-uniformity of memory accesses in typical workloads makes this situation worse. In such case, wear-leveling is often employed to map the logical address to the physical address and remap them to distribute the writes among all cells to prevent some cells from being worn out sooner than the others. This paper proposes an algebraic-mapping-based matrix wear-leveling method. Our method views the storage cells as a matrix and then levels the writes in rows and columns in a two-dimensional scheme. Every logical address is simultaneously remapped in a column and a row, and thus can be efficiently remapped to any physical address as soon as possible. The method can extend the lifetime of PCM both under normal applications and in malicious attacks, and meanwhile incur very little write overhead.更多还原