Transcript File systems under Microsoft Windows

Operating Systems’
File Systems
Ayşegül AYHAN & Can KOÇOĞLU
OUTLINE
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What is the file system ?
File systems under Unix and Unix - like systems
ext2 (Linux)
ext3(Linux)
Reiser FS (Linux)
File Systems under Mac OS X
HFS - Hierachical File System
HFS+ -Hierachical File System Plus
File Systems under Microsoft Windows
FAT 12- 16(File Allocation Table)
FAT 32(File Allocation Table)
NTFS(New Technology File System)
Conclusion
Compare of these file systems with tables
What is file system?
is a method for storing and organizing computer files
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make data easy to find and access them.
File systems under Unix and Unix - like systems
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one root directory, and every file existing under
it.
programs, device drivers, documents and
spreadsheets, keyboard, etc. are files in Unix.
avoids becoming an ungainly mess.
 This is how it works.
An example from real life
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Linux is also an Unix-like Operating System
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ext 2
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ext 3
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reiser FS
ext 2
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Previlages can be given to each of User, Group, Others.
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file system which proved itself
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Max file size 2 gb
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Max char size 255 chars
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Max volume size 4tb
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efficient if 4K blocks are used
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journal with ext3.
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Fullness of the disk not affects speed.
ext3
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Almost same as ext2 but journal property
added.
So it is called journalled file system.
Reiser FS
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journaling property
Max file size 8 tb
Max volume 16tb
High performance
Especially small files
but not much healthy..
File Systems under Mac OS X
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HFS Hierachical File System
HFS+ Hierachical File System Plus
HFS
Hierachical File System
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Similar MS-DOS and Unix with subdirectories
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Volume names max 27 chars.
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file names max 31 chars
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upper and lower case names unimportant
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All characters can be used, such as :, ?, \ …
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has two forks ; data fork, resource fork ..
HFS + is developed version of HFS
File systems under Microsoft Windows
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MS-DOS
FAT 12 (File Allocation Table)
FAT 16 (File Allocation Table)
FAT 32 (File Allocation Table)
NTFS(New Technology File System)
MS DOS
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Only Intel platforms
Not support multi-programming
Version 1 – only single directory
Version 2- more directories (hierarchical)
FAT 16
FILE ALLOCATION TABLE
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introduced way back with MS–DOS
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to handle files floppy drive
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minor modifications over the years
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can handle hard disks, even file names longer than the
original limitation.
FAT 12
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First version of FAT system
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Max file size 32 MB
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File name size 255 MB
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Max valume size 32 MB
FAT 16
Advantages
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MS-DOS Unix and Windows
accept
Has saving succesfull program
to resque folders
Has inauguration floppy if
computer is locked
To accesing data fast
partitions < 256MB
Disadvantages
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Max folder 65536.
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4GB max size to folder
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doesn't support compression,
encryption
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Lack of security…
FAT 32
FILE ALLOCATION TABLE
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enhanced version of the FAT
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used on drives from 512 megabytes (MB) to 2 TB
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partition limit is approximately 128GB
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can be accessed Win95B (OSR2, OSR2.1), Win95C (OSR2.5), Win98,
Win98SE, WinME, Win2K and WinXP
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not accessed by DOS, Windows 3.x and Windows NT 4.0
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majority of systems are formatted with FAT32 as the default.
FAT 32
Disadvantages
Advantages
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Acceptable all operating systems
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more efficient for 64 MB and less
than 64 MB memory
much more slower directories has too
many files
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Fragmantation
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more faster if folder is small or not
to big.
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Should disk fregmantation frequently
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hard to access big files
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One file size only 4GB.
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Comparing to NTFS hard disk head
moves less.Because of that it works
more efficiently on slower hard
disks.
performance
NTFS
New Technology File System
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introduced with first version of Windows NT
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completely different file system from FAT
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provides for greatly increased security, file–by–file
compression, quotas, and even encryption
NTFS
Advantages
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System performance does
not effect disorganisation
File size
performance
Small file -->fast
accessing
Disadvantages
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not suggested for less
than 64MB memory
hard disk fast is low
NTFS performance
than FAT
Conclusion
Comparison of File Systems
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Limits
Comparison of File Systems
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Metadata
Comparison of File Systems
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Features