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 ...
introduced a number of new
I/O functions to the
Microsoft 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 serv ...
line of
operating system
An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs.
Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...
s. They are intended to shorten the time taken to boot the system, improve the responsiveness of the system, and improve the reliability of data storage.
I/O subsystem
Vista modifies the behavior of
asynchronous I/O
In computer science, asynchronous I/O (also non-sequential I/O) is a form of input/output processing that permits other processing to continue before the transmission has finished. A name used for asynchronous I/O in the Windows API is overlappe ...
operations. With the new
asynchronous I/O
In computer science, asynchronous I/O (also non-sequential I/O) is a form of input/output processing that permits other processing to continue before the transmission has finished. A name used for asynchronous I/O in the Windows API is overlappe ...
APIs, a
thread, different from the one that issued the I/O request, can be notified when the operation completes. With this, a single thread can issue all the I/O requests, and then switch to a different worker thread. If this thread is the one that handles the data after the I/O request completes, then a thread-switch, which causes a performance hit, may be avoided. Windows Vista also introduces synchronous I/O cancellation. During a synchronous I/O request, the application is blocked until the request is serviced or fails. In Windows Vista the application may issue a cancellation request. Applications that cancel the operation on user feedback may prefer to enable user feedback during the time the issuing thread is suspended for usability.
Windows Vista also implements
I/O scheduling
Input/output (I/O) scheduling is the method that computer operating systems use to decide in which order I/O operations will be submitted to storage volumes. I/O scheduling is sometimes called disk scheduling.
Purpose
I/O scheduling usually ...
as prioritized I/O. Disk I/O requests in Windows Vista are assigned priorities; a higher priority request is given preferential treatment, over a request that has a lower priority, during the execution of the request. Windows Vista defines five priority classes – ''Very Low'', ''Low'', ''Normal'', ''High'' and ''Critical''. By default I/O requests are assigned ''Normal'' priority. Windows Vista also allows reservation of bandwidth on a per-application basis during disk access; this aims to guarantee the required
throughput
Network throughput (or just throughput, when in context) refers to the rate of message delivery over a communication channel, such as Ethernet or packet radio, in a communication network. The data that these messages contain may be delivered ov ...
rate to the application when it accesses the disk. Both these features are used by
Windows Media Player
Windows Media Player (WMP) is the first media player and media library application that was developed by Microsoft for playing audio, video and viewing images on personal computers running the Microsoft Windows operating system, as well as on ...
with respect to media playback.
Disk Defragmenter
Disk or disc may refer to:
* Disk (mathematics), a geometric shape
* Disk storage
Music
* Disc (band), an American experimental music band
* ''Disk'' (album), a 1995 EP by Moby
Other uses
* Disk (functional analysis), a subset of a vector sp ...
,
SuperFetch
Windows Vista introduced a number of new I/O functions to the Microsoft Windows line of operating systems. They are intended to shorten the time taken to boot the system, improve the responsiveness of the system, and improve the reliability of dat ...
,
Windows Defender
Microsoft Defender Antivirus (formerly Windows Defender) is an anti-malware component of Microsoft Windows. It was first released as a downloadable free anti-spyware program for Windows XP and was shipped with Windows Vista and Windows 7. It has ...
,
Windows Search
Windows Search (also known as Instant Search) is a content index desktop search platform by Microsoft introduced in Windows Vista as a replacement for both the previous Indexing Service of Windows 2000 and the optional MSN Desktop Search for Wind ...
, and applications that run at startup all use prioritized I/O.
Prior to Windows Vista, all I/O requests were capped at 64 KB; thus larger operations had to be completed in chunks. In Windows Vista, there is no limit on the size of I/O requests. This means an entire I/O operation can be completed by issuing fewer requests, which in turn may lead to higher performance. Windows Explorer and the
Command Prompt's ''copy'' command have been modified to issue 1 MB requests.
ReadyBoost
ReadyBoost, makes PCs running Windows Vista more responsive by using
flash memory
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...
on a
USB drive
A USB flash drive (also called a thumb drive) is a data storage device that includes flash memory with an integrated USB interface. It is typically removable, rewritable and much smaller than an optical disc. Most weigh less than . Since first ...
(USB 2.0 or 3.0 only),
SD card
Secure Digital, officially abbreviated as SD, is a proprietary non-volatile flash memory card format developed by the SD Association (SDA) for use in portable devices.
The standard was introduced in August 1999 by joint efforts between SanDis ...
,
Compact Flash
CompactFlash (CF) is a flash memory mass storage device used mainly in portable electronic devices. The format was specified and the devices were first manufactured by SanDisk in 1994.
CompactFlash became one of the most successful of the ea ...
, or other form of flash memory, in order to boost system performance. When such a device is plugged in, the Windows
Autoplay
AutoPlay, a feature introduced in Windows 98, examines newly discovered removable media and devices and, based on content such as pictures, music or video files, launches an appropriate application to play or display the content. It is closely rel ...
dialog offers an additional option to use it to speed up the system; an additional "ReadyBoost" tab is added to the drive's properties dialog where the amount of space to be used can be configured. Windows ReadyBoost is also available for Windows 7 and Windows 10. Most flash memory devices are formatted in the FAT32 format. This will need to be changed if one wants to properly utilize a larger flash device for ReadyBoost. But if one activates ReadyBoost using Windows
Autoplay
AutoPlay, a feature introduced in Windows 98, examines newly discovered removable media and devices and, based on content such as pictures, music or video files, launches an appropriate application to play or display the content. It is closely rel ...
reformatting the device will become impossible until ReadyBoost for that device is disabled.
ReadyDrive
ReadyDrive (codenamed Piton
) is a feature of Windows Vista that enables Windows Vista computers equipped with a
hybrid drive
In computing, a hybrid drive (solid state hybrid drive – SSHD) is a logical or physical storage device that combines a faster storage medium such as solid-state drive (SSD) with a higher-capacity hard disk drive (HDD). The intent is adding s ...
or other
flash memory
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...
caches (such as
Intel Turbo Memory Intel Turbo Memory is a technology introduced by Intel Corporation that uses NAND flash memory modules to reduce the time it takes for a computer to power up, access programs, and write data to the hard drive. During development, the technology was ...
) to boot up faster, resume from
hibernation
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most ...
in less time, and preserve battery power. Hybrid hard drives are a type of hard disk that integrates
non-volatile
Non-volatile memory (NVM) or non-volatile storage is a type of computer memory that can retain stored information even after power is removed. In contrast, volatile memory needs constant power in order to retain data.
Non-volatile memory typic ...
flash memory
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...
with a traditional hard drive. The drive-side functionality is expected to be standardized in
ATA-8. When a hybrid hard drive is installed in a Windows Vista machine, the operating system will display a new "NV Cache" property tab as part of the drive's device properties within the
Device Manager
Device Manager is a component of the Microsoft Windows operating system. It allows users to view and control the hardware attached to the computer. When a piece of hardware is not working, the offending hardware is highlighted for the user to d ...
.
It was reported in
eWeek
''eWeek'' (''Enterprise Newsweekly'', stylized as ''eWEEK''), formerly PCWeek, is a technology and business magazine. Previously owned by QuinStreet; Nashville, Tennessee marketing company TechnologyAdvice acquired eWeek in 2020.
The print edi ...
that the technology is not being utilized to full extent due to lack of hybrid drive-specific drivers
for the hybrid drives and instead delegated the job to the device manufacturers.
However, Microsoft rebuffed the suggestion that it was not providing specialized drivers for hybrid systems. Also, in June 2006, David Morgenstern wrote an article for eWeek suggesting that ReadyDrive might sacrifice data integrity for speed and battery savings.
Documentation from Microsoft, however, claims that a copy of the data is always maintained on the hard disk, so there is no question of data loss even if the flash cache fails.
SuperFetch
SuperFetch is a technology that pre-loads commonly used applications into memory to reduce their load times. It is extended from the "
prefetcher
The Prefetcher is a component of Microsoft Windows which was introduced in Windows XP. It is a component of the Memory Manager that can speed up the Windows boot process and shorten the amount of time it takes to start up programs. It accomplishe ...
" function in
Windows XP
Windows XP is a major release of Microsoft's Windows NT operating system. It was released to manufacturing on August 24, 2001, and later to retail on October 25, 2001. It is a direct upgrade to its predecessors, Windows 2000 for high-end and ...
. SuperFetch attempts to load commonly used libraries and application components into memory before they are required. It does so by continually analyzing application behavior and usage patterns, e.g. what applications are typically used in the morning after logon.
The cache memory is marked with low priority, meaning that if another process needs the memory, it will be given up.
By default, the necessary files are loaded into main memory, but using a feature called
ReadyBoost
ReadyBoost (codenamed EMD) is a disk caching software component developed by Microsoft for Windows Vista and included in later versions of Windows. ReadyBoost enables NAND memory mass storage CompactFlash, SD card, and USB flash drive devices to ...
, Windows Vista and Windows 7 can use alternative storage such as
USB flash drive
A USB flash drive (also called a thumb drive) is a data storage device that includes flash memory with an integrated USB interface. It is typically removable, rewritable and much smaller than an optical disc. Most weigh less than . Since firs ...
s, thereby freeing up
main memory
Computer data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers.
The central processing unit (CPU) of a computer ...
. Although hard disks may have higher sequential data transfer rates, flash drives can be faster for small files or non-sequential I/O because of their short random seek times.
ReadyBoot is a feature that complements SuperFetch by analysing only core boot processes (such as drivers) in order to speed up a computer' startup.
In
Windows 10
Windows 10 is a major release of Microsoft's Windows NT operating system. It is the direct successor to Windows 8.1, which was released nearly two years earlier. It was released to manufacturing on July 15, 2015, and later to retail on J ...
, the SuperFetch was renamed to SysMain.
Offline Files
Offline Files is a feature of Windows, introduced in
Windows 2000
Windows 2000 is a major release of the Windows NT operating system developed by Microsoft and oriented towards businesses. It was the direct successor to Windows NT 4.0, and was Software release life cycle#Release to manufacturing (RTM), releas ...
, which maintains a client-side cache of files shared over a network. It locally caches shared files marked for offline access, and uses the cached copy whenever the network connection to the remote files is interrupted. Windows Vista Business, Enterprise and Ultimate editions contain significant improvements to ''Offline Files''. Beginning with Windows Vista, whenever the connection is restored, all open file handles to the cached copy are redirected to the remote version, without waiting for the cached files to be synchronized.
This transition from online to offline and back is transparent to the clients using the file. The local copy is automatically synchronized with the remote copy, to reflect the changes made on either copy of the file. The file caching and sync algorithm has also been completely rewritten to determine the differences faster. When synchronizing the changes in the cached copy to the remote version, the ''Bitmap Differential Transfer'' protocol is used so that only the changed blocks in the cached version are transferred. This also improves support for caching large files.
The entire file is still downloaded when retrieving changes from the remote copy.
Files are synchronized on a per-share basis and encrypted on a per-user basis and users can force Windows to work in offline mode or online mode through the ''Work Offline/Online'' button in Explorer, or sync manually from the Sync Center. Sync Center can also report sync errors and resolve sync conflicts. The property page for any file or folder has an Offline Files tab that provides status and allows control of the offline status of the file or folder. Moreover, even if a single file is unavailable, other files in the same share and other shares are available as the transition is now at the share level instead of server level. Offline Files are configurable through
Group Policy
Group Policy is a feature of the Microsoft Windows NT family of operating systems (including Windows 7, Windows 8.1, Windows 10, Windows 11, and Windows Server 2003+) that controls the working environment of user accounts and computer accounts. G ...
and provide better interoperability with
DFS. Also, a comprehensive Offline Files management API is available via
COM
Com or COM may refer to:
Computing
* COM (hardware interface), a serial port interface on IBM PC-compatible computers
* COM file, or .com file, short for "command", a file extension for an executable file in MS-DOS
* .com, an Internet top-level d ...
objects and scriptability through
WMI.
Windows Vista also supports "ghosting" of online files and folders. When users make only a few files from a directory available offline, Windows Vista creates ghosted entries of the remaining unavailable items to preserve the online context. Offline Files also feature slow-link mode which when enabled through
Group Policy
Group Policy is a feature of the Microsoft Windows NT family of operating systems (including Windows 7, Windows 8.1, Windows 10, Windows 11, and Windows Server 2003+) that controls the working environment of user accounts and computer accounts. G ...
, always reads from and writes to the local cache to improve performance over a slow network connection. It is also possible in Windows Vista to specify a limit for the ''total size'' of the local cache and another sub-limit for the space used by automatically cached files. Manually cached files are never removed from the local cache even if the cache limit is reached.
In Windows XP, Offline Files could not be enabled when
Fast User Switching
Fast user switching is a feature of a multi-user operating system which allows users to switch between user accounts without quitting applications and logging out.
In Linux
The Linux kernel's VT subsystem dates back to 1993 and does not underst ...
was enabled. This restriction applied because Offline Files were synchronized at log off and Fast User Switching does not completely log off users. In Windows Vista, this restriction no longer applies as Offline Files runs as a
Windows service
In Windows NT operating systems, a Windows service is a computer program that operates in the background. It is similar in concept to a Unix daemon. A Windows service must conform to the interface rules and protocols of the Service Control Manager ...
that performs synchronization for the user at opportune times such as logon and offline to online transitions. Synchronization does not occur continuously in the background, nor does it occur at log off.
Transactional NTFS
Transactional NTFS (abbreviated TxF) 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'' se ...
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 ...
file system
In computing, file system or filesystem (often abbreviated to fs) is a method and data structure that the operating system uses to control how data is stored and retrieved. Without a file system, data placed in a storage medium would be one larg ...
, allowing Windows application developers to write file output routines that are guaranteed to either completely succeed or completely fail. Transactional NTFS allows for files and directories to be created, renamed, and deleted atomically. Using a transaction 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.
Shadow Copy
A number of Microsoft Windows components have been updated to make use of Shadow Copy. The
Backup and Restore Center
Backup and Restore (formerly Backup and Restore Center) is the primary backup component of Windows Vista and Windows 7. It can create file and folder backups, as well as system images backups, to be used for recovery in the event of data corrup ...
in Windows Vista and later performs block-based backups when doing full system backups. The file backup feature also uses shadow copy but stores files inside ZIP files.
Beginning with
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 ...
, Shadow Copy is also used by the ''System Protection'' component which creates and maintains periodic copies of system and user data on the same local volume (similar to the Shadow Copies for Shared Folders feature in Windows Server) but allows it to be locally accessed by
System Restore
System Restore is a feature in Microsoft Windows that allows the user to revert their computer's state (including system files, installed applications, Windows Registry, and system settings) to that of a previous point in time, which can be used ...
.
System Restore
System Restore is a feature in Microsoft Windows that allows the user to revert their computer's state (including system files, installed applications, Windows Registry, and system settings) to that of a previous point in time, which can be used ...
allows reverting to an entire previous set of shadow copies called a ''Restore point''. Prior to Windows Vista,
System Restore
System Restore is a feature in Microsoft Windows that allows the user to revert their computer's state (including system files, installed applications, Windows Registry, and system settings) to that of a previous point in time, which can be used ...
was based on a file-based filter that watched changes for a certain set of file extensions, and then copied files before they were overwritten.
Additionally, a property sheet
shell extension
File Explorer, previously known as Windows Explorer, is a file manager application that is included with releases of the Microsoft Windows operating system from Windows 95 onwards. It provides a graphical user interface for accessing the fil ...
called ''Previous Versions'' allows restoring individual files or folders locally from the restore point, as they existed at the time of the snapshot, thus retrieving an earlier version of a file or recovering a file deleted by mistake.
The shadow copy is not created every time a file is changed; backup copies are created automatically once per day, or manually when triggered by the backup utility or installer applications which create a ''restore point''. The "Previous Versions" feature is available in the Business, Enterprise, and Ultimate
editions of Windows Vista.
Folder redirection
Windows Vista introduces the ability to independently redirect up to 10
user profile
A user profile is a collection of settings and information associated with a user. It contains critical information that is used to identify an individual, such as their name, age, portrait photograph and individual characteristics such as ...
sub-folders to a network location.
There is also a
Management Console snap-in in Windows Vista to allow users to configure ''Folder Redirection'' for clients running Windows Vista, Windows XP, and Windows 2000.
exFAT
Windows Vista Service Pack 1 introduced support for the
exFAT
exFAT (Extensible File Allocation Table) is a file system introduced by Microsoft in 2006 and optimized for flash memory such as USB flash drives and SD cards. exFAT was proprietary until 28 August 2019, when Microsoft published its specificati ...
file system.
See also
*
Features new to Windows Vista
Compared with previous versions of Microsoft Windows, features new to Windows Vista are very numerous, covering most aspects of the operating system, including additional management features, new aspects of security and safety, new I/O techno ...
*
BitLocker Drive Encryption
BitLocker is a full volume encryption feature included with Microsoft Windows versions starting with Windows Vista. It is designed to protect data by providing encryption for entire Volume (computing), volumes. By default, it uses the Advanced E ...
*
Protected Media Path
The Protected Media Path is a set of technologies creating a "Protected Environment," first included in Microsoft's Windows Vista operating system, that is used to enforce digital rights management (or DRM) protections on content.
Its subsets are ...
*
ACID
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...
References
{{DEFAULTSORT:Windows Vista I O technologies
Windows Vista
Microsoft application programming interfaces
Windows NT architecture