Transactional NTFS (abbreviated TxF) is a component introduced in

Windows Vista Windows Vista is a major release of the Windows NT operating system developed by Microsoft. It was the direct successor to Windows XP, which was released five years before, at the time being the longest time span between successive releases of ...

and present in later versions of the

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Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for se ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

that brings the concept of

atomic transaction In database systems, atomicity (; from grc, ἄτομος, átomos, undividable) is one of the ACID (''Atomicity, Consistency, Isolation, Durability'') transaction properties. An atomic transaction is an ''indivisible'' and '' irreducible' ...

s to the

NTFS New Technology File System (NTFS) is a proprietary journaling file system developed by Microsoft. Starting with Windows NT 3.1, it is the default file system of the Windows NT family. It superseded File Allocation Table (FAT) as the preferred fil ...

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, allowing Windows application developers to write file-output routines that are guaranteed to either succeed completely or to fail completely. Major operating system components, including

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Task Scheduler Task Scheduler (formerly Scheduled Tasks) is a job scheduler in Microsoft Windows that launches computer programs or scripts at pre-defined times or after specified time intervals. Microsoft introduced this component in the Microsoft Plus! for W ...

, and

Windows Update Windows Update is a Microsoft service for the Windows 9x and Windows NT families of operating system, which automates downloading and installing Microsoft Windows software updates over the Internet. The service delivers software updates for ...

, rely on TxF for stability. During the

development of Windows Vista The New product development, development of Windows Vista occurred over the span of five years, starting in earnest in May 2001, prior to the release of Microsoft's Windows XP operating system, and continuing until November 2006. Microsoft origin ...

WinFS WinFS (short for Windows Future Storage) was the code name for a canceled data storage and management system project based on relational databases, developed by Microsoft and first demonstrated in 2003 as an advanced storage subsystem for the Micro ...

also relied on TxF for storing files. Due to its complexity and various nuances which developers need to consider as part of application development, Microsoft has deprecated TxF and stated that it may be removed in a future version of Windows. Microsoft has strongly recommended that developers investigate using the alternatives rather than adopting the Transactional NTFS API platform which may not be available in future versions of Windows.

Overview

Transactional NTFS allows for files and directories to be created, modified, renamed, and deleted atomically. Using transactions ensures correctness of operation; in a series of file operations (done as a transaction), the operation will be committed if all the operations succeed. In case of any failure, the entire operation will roll back and fail. Transactional NTFS is implemented on top of the

Kernel Transaction Manager Kernel Transaction Manager (KTM) is a component of the Windows operating system kernel in Windows Vista and Windows Server 2008 that enables applications to use atomic transactions on resources by making them available as kernel objects. Overview ...

, which is a Windows kernel component introduced in Windows Vista that provides transactioning of objects in the kernel. The NTFS file system already supports journaling of low-level operations, such as writing a block of data. Transactional NTFS expands on this capability to include: * Atomic operations on a single file: A common example of this is saving a file from an application; if the application or machine were to crash while writing the file, then only part of the file could be written, possibly resulting in a corrupted file. This would be a very significant problem if a previous version of the file was being over-written, as data would likely be lost. * Atomic operations spanning multiple files: If an application needs to update several files at once with a set of changes, all the necessary file operations can be performed as a single transaction, preventing inconsistent updates in the event of a failure. * Atomic operations spanning multiple computers: Performing the same operation on multiple computers is a fairly common administrative task in a corporate network; Transactional NTFS integrates with the

Distributed Transaction Coordinator The Microsoft Distributed Transaction Coordinator (MSDTC) service is a component of modern versions of Microsoft Windows that is responsible for coordinating transactions that span multiple resource managers, such as databases, message queues, and ...

to ensure that the change is successfully applied to all machines. With the exception of read operations, using Transactional NTFS for transactions on

Encrypting File System The Encrypting File System (EFS) on Microsoft Windows is a feature introduced in version 3.0 of NTFS that provides filesystem-level encryption. The technology enables files to be transparently encrypted to protect confidential data from attackers ...

files is not supported in Windows Vista until Service Pack 1 and

Windows Server 2008 Windows Server 2008 is the fourth release of the Windows Server operating system produced by Microsoft as part of the Windows NT family of the operating systems. It was released to manufacturing on February 4, 2008, and generally to retail on F ...

References

External links

Because We Can
a Microsoft developer blog that discusses TxF both conceptually and in code
Kernel Transaction Manager
documentation on the Microsoft Developer Network. {{Windows Components Transaction processing Windows components Windows Vista Microsoft application programming interfaces

Overview

See also

References

External links