Computer File Systems

©Richard Goldman

November 26, 2001

• FAT12

• FAT16

• FAT32

• NTFS

• WinFS

• HPFS

FAT12

• Used on small disks• Supported by:

– DOS– Win 3X– Win 95– Win 98– Win Me– Win NT– Win 2000– Win XP

FAT16• Max partition size 4GB (64KB cluster)

• Max recommended partition size 2GB – some utilities will have problems with partitions over 2GB. (32K cluster)

• Max of 512 entries in root directory

• Max 2GB file size

• Supported by:– DOS

– Win 3X

– Win 95

– Win 98

– Win Me

– Win NT

– Win 2000

– Win XP

– OS/2

– UNIX

FAT32

• Max partition size – 2TB• Min partition size – 512MB• Win 2000 can support and access partitions up to

2TB but will only create partitions up to 32GB.• Supported By:

– Win 95 OSR2 (B)– Win Me– Win 2000– Win XP

NTFS

• Windows NT 4.0 uses Ver 1.1– (also called Ver 4.0)– Service Pack 4 .0 add ability to access Ver 5.0

• Windows 2000 uses NTFS Ver 5.0

• Max partition size – 16EB

NTFS 5.0 Features

• Reparse Points: Files and directories can have actions associated

• Improved Security and Permissions:

• Change Journals: Disk volumes can be set to keep track of all operations performed on the files and directories they contain.

• Encryption: NTFS 5.0 allows you to encrypt files and automatically decrypt them as they are read.

• Disk Quotas: Administrators can track how much disk space is being used by users or groups of users, and even limit disk space use if necessary.

• Sparse File Support: To save space on the disk, support was added for the more efficient storage of sparse files, which are large files that are mostly empty.

• Disk Defragmenter:

WinFS Features

• WinFS (Windows Future Storage )• Will be introduced with:

– file management and searching features in Longhorn (code-named for next version of Microsoft Windows)

– “…new file system with enhanced storage capabilities” – “radically improves file management and searching

features in Windows ”• Will be an add on to:

– Windows 2003 Server• Windows Future Storage Services• Windows Storage Full-Text Index