Implementing Rank Modulation
نویسندگان
چکیده
The density of NAND flash grows at the price of significantly reduced reliability. To enable the continued scaling of flash memory more fundamental changes are needed. In this paper, we show that existing flash is much more reliable by adopting the rank modulation (RM) scheme [2]. RM encodes data using the relative orders of memory cell voltages, which is inherently resilient to asymmetric errors. However, the practical performance of RM is still unknown due to the lack of implementation studies. This work has multiple contributions on the practical aspects of RM, which include: 1) Adaptations that make RM implementable using existing NAND flash memories. 2) Characterization of the first RM implementation using 20nm MLC from two vendors. 3) An application of RM to archival storage, and its performance evaluation using 16nm MLC. 4) An implementation-friendly VLSI architecture of an NAND flash memory based on RM.
منابع مشابه
On Rank Modulation Codes
We survey rank modulation codes based on a recent result by Mazumdar, Barg and Zemor [MBZ13]. The main results are explicit constructions of rank modulation codes that approach the bounds given by Barg and Mazumdar [BM10].
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