Dear DRAM:Discard Weak Rows for Reducing DRAMs Refresh Overhead

摘要：

　　Due to leakage current,DRAM devices need periodic refresh operations to maintain the validity of data in each DRAM cell.The shorter refresh period is,the more refresh overhead DRAM devices have to amortize.Since the retention time of DRAM cells are different because of process variation,DRAM providers usually set default refresh period as the retention time of those weakest cells that account for less than 0.1%of total capacity.In this paper,we propose Dear DRAM(Discard weak rows DRAM),an efficient refresh approach that is able to substantially reduce refresh overhead using two mechanisms: selectively disabling weak rows and remapping their physical addresses to a reserved region.Dear DRAM allows DRAM devices to perform refresh operations with a much longer period(increasing from 64ms to 256 ms),which reduces energy consumption.It is worth noting that compared to previous schemes,Dear DRAM is easy to be implemented,does not modify DRAM chip and only introduces slight modifications to memory controller.Experimental results show that Dear DRAM can save refresh energy an average of 76.12%,save total energy about 12.51%and improve IPC an average of 4.56%in normal temperature mode.

关键词： DRAM Memory controller Refresh Weak cell

作者: Xusheng Zhan Yungang Bao Ninghui Sun

作者单位: State Key Laboratory of Computer Architecture,ICT,CAS,Beijing,China;University of Chinese Academy of State Key Laboratory of Computer Architecture,ICT,CAS,Beijing,China

会议类型: 国际会议

会议名称: the 12th Conference on Advanced Computer Architecture?(ACA 2018)(2018年全国计算机体系结构学术年会)

会议地点: 辽宁营口

会议语种:英文

页码: 109-124

在线出版日期: 2018-08-10（万方平台首次上网日期，不代表论文的发表时间）