한국정보과학회논문지:컴퓨팅의 실제 및 레터 (Journal of KIISE:Computing Practices and Letters)

한국정보과학회 (Korean Institute of Information Scientists and Engineers)
권호 표지

향상된 혼합 사상기법을 이용한 효율적인 대블록 플래시 메모리 변환계층 설계 및 구현

Design and Implementation of an Efficient FTL for Large Block Flash Memory using Improved Hybrid Mapping

  • 발행 : 2009.01.15
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⟨ 이전 논문 다음 논문 ⟩

초록

플래시 메모리는 크기가 작고, 적은 전력을 사용하며 충격에 강하기 때문에 MP3 플레이어, 핸드폰, 디지털 카메라와 같은 휴대용 기기에서 저장장치로 널리 사용되고 있다. 플래시 메모리의 많은 장점 때문에 개인용 컴퓨터 및 노트북에서 사용되는 저장장치인 하드디스크를 플래시 메모리로 대체하고자 하는 연구도 진행되고 있다. 플래시 메모리는 덮어쓰기가 허용되지 않으며 읽기/쓰기의 기본 단위와 삭제의 기본 단위가 다르기 때문에 FTL(Flash Translation Layer)라는 플래시 변환 계층을 사용한다. 최근에는 기존의 플래시 메모리와 다른 물리구조와 특성을 갖는 대블록 플래시 메모리가 등장하여 기존의 FTL을 그대로 사용하게 되면 플래시 메모리를 효율적으로 사용할 수 없다. 본 논문에서는 기존의 FTL 중 가장 좋은 성능을 내는 FAST(Fully Associative Sector Translation)을 기반으로 데이타블록 내에서 페이지단위 사상을 적용하여 대블록 플래시 메모리의 특성에 맞는 FTL 기법을 제안한다.

Flash memory is widely used as a storage medium of mobile devices such as MP3 players, cellular phones and digital cameras due to its tiny size, low power consumption and shock resistant characteristics. Currently, there are many studies to replace HDD with flash memory because of its numerous strong points. To use flash memory as a storage medium, FTL(Flash Translation Layer) is required since flash memory has erase-before-write constraints and sizes of read/write unit and erase unit are different from each other. Recently, new type of flash memory called "large block flash memory" is introduced. The large block flash memory has different physical structure and characteristics from previous flash memory. So existing FTLs are not efficiently operated on large block flash memory. In this paper, we propose an efficient FTL for large block flash memory based on FAST(Fully Associative Sector Translation) scheme and page-level mapping on data blocks.

키워드

참고문헌

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