Abstract:

Phase Change Memory（PCM） has excellent characteristics such as high integration, low power consumption, non-volatile, etc. It is one of the most potential storage media as non-volatile memory. But, how to reduce its write delay and increase its service life is an urgent problem to be solved when PCM is used as a non-volatile memory. Thus this study proposes an independent writing method, RSIW（Reset and Set Independently Write）. This method changes the strategy that reset and set are performed simultaneously in one writing cycle in the writing scheme of the prior art scheme, so that the writing speed of the phase change memory is significantly improved. At the same time, RSIW can also combine the wear-leveling strategy to effectively balance the write frequency of each block. The writing method and implementation details of independent writing and erasing are described in the article, and the similar schemes of using phase-change memory to erase and write asymmetry are compared. Finally, the gem5 simulator is used to test. According to the experimental results, the method compares similar methods. The technology can improve the operating efficiency of the system by 37.1%~69.1%.

Key words: phase change memory, asymmetry of set and reset, wear leveling, write latency

摘要：

相变存储器具有集成度高、功耗低、非易失等优良特性，是作为非易失性内存最有潜力的存储介质之一。如何降低其写入延时和增加其使用寿命，是PCM作为非易失性内存时亟需解决的问题。为此，提出利用相变存储器擦除和写入时间不对称的特点擦写独立的写入方法，RSIW（Reset and Set Independently Write）。该方法不同于传统的写入方案，将写和擦的操作分离，让慢速的写操作在空闲时进行，使得相变存储器的写入速度获得显著提升。同时，RSIW还能结合磨损均衡的策略，有效地均衡各个块的写入频率。对擦写独立的写入方法和实施细节进行了描述，对比了同类使用相变存储器擦写不对称性进行优化的方案，最后使用gem5仿真器进行了实验，根据实验结果，该方法对比同类的技术能将系统的运行效率提高37.1%~69.1%。

关键词: 相变存储器, 擦写不对称性, 磨损均衡, 写入延时