The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Design of an Efficient FTL Algorithm Exploiting Locality Based on Sector-level Mapping

Locality를 이용한 섹터 매핑 기법의 효율적인 FTL 알고리듬

  • 홍수진 (서강대학교 전자공학과 CAD & ES 연구실) ;
  • 황선영 (서강대학교 전자공학과 CAD & ES 연구실)
  • Received : 2011.05.11
  • Accepted : 2011.06.23
  • Published : 2011.07.30
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Abstract

This paper proposes a novel FTL (Flash Translation Layer) algorithm employing sector-level mapping technique based on locality to reduce the number of erase operations in flash memory accesses. Sector-level mapping technique shows higher performance than other mapping techniques, even if it requires a large mapping table. The proposed algorithm reduces the size of mapping table by employing dynamic table update, processes sequential writes by exploiting sequential locality and extracts hot sector in random writes. Experimental results show that the number of erase operations has been reduced by 75.4%, 65.8%, and 10.3% respectively when compared with well-known BAST, FAST and sector mapping algorithms.

본 논문은 플래쉬 메모리 접근 시 소거 횟수를 줄이기 위해서 섹터 매핑 기법을 바탕으로 지역성(Locality)을 FTL (Flash Translation Layer) 알고리듬을 제안한다. 섹터 매핑 기법은 다른 기존의 매핑 기법보다 성능은 우수하나, 매핑 테이블이 커지는 단점을 가진다. 제안한 알고리듬에서는 동적 테이블 업데이트 방식으로 매핑 테이블의 크기를 줄였으며, 순차적 지역성 (Sequential Locality)을 이용하여 순차쓰기를 처리하고 임의쓰기에서 hot 섹터를 추출하였다. 실험결과 제안된 알고리듬은 기존의 BAST, FAST, 섹터 매핑 알고리듬과 비교하여 75.2%, 65.8%, 10.3%의 소거 횟수가 감소함을 보인다.

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References

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