# Exploiting Data Similarity to Improve SSD Read Performance
## 6 Conclusions  
Motivated by the observation of under-utilization issues in parallel units, such as channels and NAND flash chips, as well as the phenomenon of data duplication, we have developed a data similarity Flash Translation Layer to address the read access conflict problem. Our approach is based on the principle that the FTL distributes page-sized data with identical content across different parallel units and records this information in the mapping table. In DS-FTL, we introduce two novel schemes. The first is the content-aware page allocation scheme, which optimizes storage efficiency and reduces conflicts by intelligently allocating physical addresses based on content similarity. The second is the multi-path read scheme, which improves read performance and utilizes SSD resources effectively by allowing data to be read from any available idle channel or chip through a mapping table lookup for LPNs with multiple corresponding PPNs. This allows for the alleviation of read access conflicts by enabling data to be read from multiple alternative pages in different parallel units. We conducted a series of experiments to evaluate our proposed scheme, and the results demonstrate that it achieves an average read performance improvement of up to 35.3%. Our research is dedicated to enhancing the parallelism and read performance which ignore high-density NAND flash-based SSDs. As high-density NAND flash becomes the mainstream technology, identifying a feasible method of employing DS-FTL in high-density NAND flash-based SSDs has become a key issue, where high-density NAND flash (e.g., TLC, QLC and PLC) exhibits high latency and renders byte-to-byte comparison unacceptable for inline deduplication. We intend to devote our efforts to developing more effective data deduplication schemes for high-density NAND flash-based SSDs.  
Software, Z.Z.; Investigation, W.W.; Experiment, Z.Z.; Data curation, Y.H.; Writing--original draft, J.N.; Writing--review & editing, S.N.; Visualization, C.S. All authors have read and agreed to the published version of the manuscript.  
This work is supported by the No.5 Project: Research on container-based spaceborne lightweight edge cloud technology funded by the Shanghai Key Laboratory of Satellite Network, Shanghai Satellite Network Research Institute Co., Ltd. and China Satellite Network Innovation Co., Ltd., in part by the National Science Foundation of China under Grant 61972311, and in part by the Shandong Provincial Natural Science Foundation, China under Grant ZR2021 LZH009.  
Not applicable.  
Data Availability Statement: Data is contained within the article.  
The authors would like to thank the reviewers for their thoughtful comments and efforts toward improving our manuscript.  
Author [PERSON] was employed by the company China Satellite Network Innovation Co., Ltd., author [PERSON] was employed by the company Shanghai Key Laboratory of Satellite Network, Shanghai Satellite Network Research Institute Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.