Analysis and Comparison of NAND Flash Specific File Systems *

Abstra c t N A N D fla sh m emory b ecomes one of the most popula r s t o rage d e vice s in e m bed d e d sy stem a n d m ob ile computers. Efficient flash fil e sy stem designs are important for sy st e m d esigners a n d use r s . In t his p aper, w e s t u d y the d esign issues and p erforma n ce of flash-specific fil e systems a n d d efine four p e rfo rmance metrics t o evaluate fla sh fil e systems. Then, d e t aile d comparisons o f three m ains t r eam flash fil e systems are conducted, including JFFS2 , Y A F F S2 a n d UBIFS . Taking t ech n iqu e s used in the thre e fil e systems a n d e va luatio n r es u lts int o accou n t , fla sh fil e system d esig n s p ace is d is cussed . T h is paper can provide u sers a comprehensi ve understanding o f NAND fla sh fil e system d e si gn, present guidelines for measu rem ent of fla sh file systems a n d help use r s d e t e r min e w hich fil e sy stem best m ee t s their n eed.