An Performance Optimization Scheme for Flash Memory System in 6G Mobile Network: Bit Remapping
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摘要: 第6代移动通信技术(6G)网络所产生的海量数据对数据存储带来了全新挑战,推动着存储技术的迅猛发展。与非门(NAND)闪存存储器具有读写速度快,可靠性高等优点,故在6G网络中具有广泛的应用前景。为了提高NAND闪存的可靠性,针对两种不同位线结构的错误特性,该文分别提出基于全位线结构的等精度重映射方案和基于奇偶位线结构的不等精度的重映射方案。仿真结果表明,两种新型比特重映射方案有效提升了闪存的误码性能。基于此,该文所提重映射技术可被视作6G网络中可靠而高效的存储优化技术。Abstract: The massive data generated by the sixth generation mobile communication technology (6G) network brings new challenges to data storage, which promotes further the rapid development of storage technology. Not AND (NAND) flash memory has the advantages of fast reading/writing speed and high reliability, and hence it possesses a wide application prospect in the 6G network. To improve the reliability of NAND flash memory, according to the error characteristics of two different bit-line structures, an all-bit-line-structure-aided equal-precision remapping scheme and an odd-even-bit-line-structure-aided unequal-precision remapping scheme are proposed. Simulation results show that the two new remapping schemes improve effectively the bit error performance of flash memory. Therefore, the remapping technology proposed in this paper can be regarded as a reliable and efficient storage optimization technology for 6G network.
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Key words:
- 6G network /
- Data storage /
- All bit-line structure /
- Odd-even bit-line structure /
- Bit remapping
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表 1 新型全位线结构重映射方案(算法1)
输入:原始数据${D_{\text{R}}}$ 输出:重映射后的数据$ D_{\text{R}}' $ (1) 获取原始数据${D_{\text{R}}}$; (2) 将${D_{\text{R}}}$划分成$N$个数据段${S_1},{\text{ }}{S_2},\cdots,{\text{ }}{S_N}$; (3) for 数据段${S_n}{\text{ (}}n \in \{ 1,{\text{ }}2,\cdots,{\text{ }}N\} {\text{)}}$ do (4) 统计MSB页上1的比例:${R_{{\text{MSB}}}}$; (5) if ${R_{{\text{MSB}}}} < 50\% $,then (6) 对MSB页上的数据执行比特翻转操作; (7) 分别统计对应MSB页为1和0时LSB页上1的比例:
${L^{{\text{MSB = 1}}}},{L^{{\text{MSB = 0}}}}$;(8) if ${L^{{\text{MSB = 1}}}} < 50\% $,then (9) 对$ {\text{MSB}} = 1 $对应的LSB页数据执行比特翻转操作; (10) if ${L^{{\text{MSB = 0}}}} > 50\% $,then (11) 对$ {\text{MSB}} = 0 $对应的LSB页数据执行比特翻转操作; (12) 记录标志位 (13) end (14) 输出重映射后的数据$ D_{\text{R}}' $; (15) 结束 表 2 新型奇偶位线结构重映射方案(算法2)
输入:原始数据${D_{\text{R}}}$ 输出:重映射后的数据$ D_{\text{R}}' $ (1) 获取原始数据${D_{\text{R}}}$,其中偶单元中的数据为$ D_{\text{R}}^{{\text{even}}} $,奇单元的
数据为$ D_{\text{R}}^{{\text{odd}}} $;(2) 将$ D_{\text{R}}^{{\text{even}}} $划分成$N$个数据段:$S_1^{{\text{even}}},{\text{ }}S_2^{{\text{even}}},\cdots,{\text{ }}S_N^{{\text{even}}}$,将
$ D_{\text{R}}^{{\text{odd}}} $划分成$M$ ($ M > N $)个数据段$S_1^{{\text{odd}}},{\text{ }}S_2^{{\text{odd}}},\cdots,{\text{ }}S_M^{{\text{odd}}}$;(3) for $ S_n^{{\text{even}}}{\text{ (}}n \in \{ 1,{\text{ }}2,\cdots,{\text{ }}N\} ) $ do (4) 统计MSB页上1的比例$M_n^{{\text{even}}}$; (5) if $M_n^{{\text{even}}} < 50\% $,then (6) 对MSB页数据执行比特翻转操作; (7) 统计对应MSB页为1和0时LSB页上1的比例
${L^{{\text{MSB = 1}}}},{L^{{\text{MSB = 0}}}}$(8) if ${L^{{\text{MSB = 1}}}} < 50\% $,then (9) 对$ {\text{MSB = 1}} $对应的LSB页数据执行比特翻转操作; (10) if ${L^{{\text{MSB = 0}}}} > 50\% $,then (11) 对$ {\text{MSB = 0}} $对应的LSB页数据执行比特翻转操作; (12) 记录标志位 (13) end (14) for $S_m^{{\text{odd}}}{\text{ (}}m \in \{ 1,{\text{ }}2,\cdots,{\text{ }}M\} )$ do (15) 统计MSB页上1的比例$M_m^{{\text{odd}}}$; (16) if $M_m^{{\text{odd}}} < 50\% $,then (17) 对MSB页数据执行比特翻转操作; (18) 统计对应MSB页为1和0时LSB页上1的比例
${L^{{\text{MSB = 1}}}},{L^{{\text{MSB = 0}}}}$(19) if ${L^{{\text{MSB = 1}}}} < 50\% $,then (20) 对$ {\text{MSB = 1}} $对应的LSB页数据执行比特翻转操作; (21) if ${L^{{\text{MSB = 0}}}} > 50\% $,then (22) 对$ {\text{MSB = 0}} $对应的LSB页数据执行比特翻转操作; (23) 记录标志位 (24) end (25) 输出重映射后的数据$ D_{\text{R}}' $; (26) 结束 -
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