Janus-FTL Adjusting the Size of Page and Block Mapping Areas using Reference Pattern

참조 패턴에 따라 페이지 및 블록 사상 영역의 크기를 조절하는 Janus-FTL

  • 권훈기 (서울시립대학교 컴퓨터고학부) ;
  • 김은삼 (홍익대학교 정보컴퓨터공학부) ;
  • 최종무 (단국대학교 컴퓨터학과) ;
  • 이동희 (서울시립대학교 컴퓨터고학부) ;
  • 노삼혁 (홍익대학교 정보컴퓨터공학부)
  • Published : 2009.12.15


Naturally, block mapping FTL works well for sequential writes while page mapping FTL does well for random writes. To exploit their advantages, a practical FTL should be able to selectively apply a suitable scheme between page and block mappings for each write pattern. To meet that requirement, we propose a hybrid mapping FTL, which we call Janus-FTL, that distributes data to either block or page mapping areas. Also, we propose the fusion operation to relocate the data from block mapping area to page mapping area and the defusion operation to relocate the data from page mapping area to block mapping area. And experimental results of Janus-FTL show performance improvement of maximum 50% than other hybrid mapping FTLs.


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