Transaction-Safe FAT File System
Encyclopedia
Transaction-Safe FAT File System (TFAT) refers to two file system
s used in Microsoft
products to provide transaction-safety for data stored on a disk. The goal is to reduce the risk of data loss in cases of power loss or unexpected removal of the drive. The latter problem has become more common with the spread of USB drives.
file system that maintained two copies (FAT0 and FAT1) of the file allocation table instead of just one. While performing a drive operation, changes would be made to FAT1. When the operation was complete, the FAT1 table would be copied to FAT0, updating the stable view of the file system.
file system as the base file system instead of FAT. Introduced with Windows Embedded CE 6.0, it replaced TFAT, and is frequently referred to as TFAT, which can lead to confusion with the original TFAT described above.
The use of exFAT as the underlying file system allows for larger files and larger partitions. TexFAT requires a hardware-specific driver designed for the type of media on which the TexFAT volume resides.
s, neither form of TFAT is recommended for removable media. While the desktop OS could still read the drive, it could not use the transaction-safe features, so unexpected removal or a power outage could lead to data loss. In addition, directories created under the desktop OS may not be transaction-safe even if the drive is later attached to a TFAT aware OS.
File system
A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...
s used in Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
products to provide transaction-safety for data stored on a disk. The goal is to reduce the risk of data loss in cases of power loss or unexpected removal of the drive. The latter problem has become more common with the spread of USB drives.
Original
The original form of TFAT was a driver layer modification to the original FATFile Allocation Table
File Allocation Table is a computer file system architecture now widely used on many computer systems and most memory cards, such as those used with digital cameras. FAT file systems are commonly found on floppy disks, flash memory cards, digital cameras, and many other portable devices because of...
file system that maintained two copies (FAT0 and FAT1) of the file allocation table instead of just one. While performing a drive operation, changes would be made to FAT1. When the operation was complete, the FAT1 table would be copied to FAT0, updating the stable view of the file system.
TexFAT
The Transaction-Safe Extended FAT File System (TexFAT), TexFAT provides similar functionality to the original TFAT using the exFATExFAT
exFAT is a proprietary, patent-pending file system designed especially for USB flash drives. Developed by Microsoft, it is supported in Windows XP and Windows Server 2003 with update KB955704, Windows Embedded CE 6.0, Windows Vista with Service Pack 1, Windows Server 2008, Windows 7, Windows...
file system as the base file system instead of FAT. Introduced with Windows Embedded CE 6.0, it replaced TFAT, and is frequently referred to as TFAT, which can lead to confusion with the original TFAT described above.
The use of exFAT as the underlying file system allows for larger files and larger partitions. TexFAT requires a hardware-specific driver designed for the type of media on which the TexFAT volume resides.
Limitations
Due to the lack of support in desktop operating systemOperating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s, neither form of TFAT is recommended for removable media. While the desktop OS could still read the drive, it could not use the transaction-safe features, so unexpected removal or a power outage could lead to data loss. In addition, directories created under the desktop OS may not be transaction-safe even if the drive is later attached to a TFAT aware OS.