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http://dx.doi.org/10.14372/IEMEK.2020.15.1.9

An In-Depth Analysis and Improvement on Cache Mechanisms of SSD FTL  

Lee, Hyung-Bong (Gangneung-Wonju National University)
Chung, Tae-Yun (Gangneung-Wonju National University)
Publication Information
IEMEK Journal of Embedded Systems and Applications / v.15, no.1, 2020 , pp. 9-16 More about this Journal
Abstract
Recently, the capacity of SSD has been increasing rapidly due to the improvement of flash memory density. To take full advantage of these SSDs, first of all, FTL's prompt adaptation is necessary. The FTL is a translation layer existing in SSDs to overcome the drawback of the SSD that cannot be modified in place, and has garbage collection and caching functions in addition to the map table management function. In this study, we focus on caching function, compare and analyze the cache implementation methodologies, and propose improved methods. Typical cache implementations divide the cache into groups, manage and retrieve the caches in the group as a linked list. Thus, searches are made in the order of the linked list. In contrast, we propose a method of sequential searching using the search area group of a cache registered in the map table regardless of the linked list and cache group. Experimental results show that the proposed method has a 2.5 times improvement over the conventional method.
Keywords
SSD; FTL(Flash Translation Layer); Cache group; Linked list; B tree;
Citations & Related Records
Times Cited By KSCI : 6  (Citation Analysis)
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