Windows Vista I/O technologies
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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 data storage.
I/O subsystem
Vista modifies the behavior of
Windows Vista also implements
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
ReadyBoost
ReadyBoost, makes PCs running Windows Vista more responsive by using
ReadyDrive
ReadyDrive (codenamed Piton
It was reported in eWeek that the technology is not being utilized to full extent due to lack of hybrid drive-specific drivers[9] for the hybrid drives and instead delegated the job to the device manufacturers.[9] However, Microsoft rebuffed the suggestion that it was not providing specialized drivers for hybrid systems.[10] Also, in June 2006, David Morgenstern wrote an article for eWeek suggesting that ReadyDrive might sacrifice data integrity for speed and battery savings.[11] 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.[11][12]
SuperFetch
SuperFetch is a technology that pre-loads commonly used applications into memory to reduce their load times. It is extended from the "prefetcher" function in Windows XP. 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.[13] 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
ReadyBoot is a feature that complements SuperFetch by analysing only core boot processes (such as drivers) in order to speed up a computer' startup.[14]
In Windows 10, the SuperFetch was renamed to SysMain.
Offline Files
Offline Files is a feature of Windows, introduced in Windows 2000, 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.[15] 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.[15] 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 and provide better interoperability with DFS. Also, a comprehensive Offline Files management API is available via COM 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
In Windows XP, Offline Files could not be enabled when
Transactional NTFS
Transactional NTFS (abbreviated TxF) brings the concept of
Shadow Copy
A number of Microsoft Windows components have been updated to make use of Shadow Copy. The
Beginning with Windows Vista, 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 allows reverting to an entire previous set of shadow copies called a Restore point. Prior to Windows Vista, System Restore 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.[17]
Additionally, a property sheet
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.[18] The "Previous Versions" feature is available in the Business, Enterprise, and Ultimate editions of Windows Vista.[19]
Folder redirection
Windows Vista introduces the ability to independently redirect up to 10 user profile sub-folders to a network location.[20] 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 file system.
See also
- Features new to Windows Vista
- BitLocker Drive Encryption
- Protected Media Path
- ACID
References
- ^ I/O Prioritization in Windows Vista
- ^ a b Russinovich, Mark. "Inside the Windows Vista Kernel: Part 1". TechNet. Microsoft. Retrieved July 15, 2015.
- ^ Aul, Gabriel (2006). "Windows Vista Performance Technologies" (PPT). Microsoft. Retrieved July 9, 2015.
- ^ Tom Archer (April 14, 2006). "ReadyBoost - Using Your USB Key to Speed Up Windows Vista". Tom Archer's Blog. Microsoft. Retrieved 2006-05-21.
- ^ Nicholson, Clark (2004). "Improved Disk Drive Power Consumption Using Solid-State Non-Volatile Memory". Microsoft. Archived from the original (PPT) on May 9, 2006. Retrieved December 6, 2015.
- ^ Moulster, Ian (April 6, 2006). "SuperFetch, ReadyBoost and ReadyDrive: some new feature names for you". MSDN Blogs. Microsoft. Retrieved September 17, 2015.
- ^ Mark Russinovich. "Inside the Windows Vista kernel, part II". Retrieved 2008-08-31.
- ^ Kleef, Michael (November 24, 2007). "Its arrived! The Lenovo T610 is here...with a hybrid drive!". MSDN Blogs. Microsoft. Retrieved December 12, 2015.
- ^ a b "Without Drivers, Hybrid HDDs Delayed". eWeek. Retrieved 2007-07-21.
- ^ Chris Preimesberger. "Vista Supports Hybrid Storage Drives, Microsoft Says". Retrieved 2007-07-22.
- ^ a b David Morgenstern (June 10, 2006). "Is Vista Heading for a Flash Nightmare?". eWeek. Retrieved 2007-02-22.
- ^ "Windows ReadyDrive". Microsoft. Retrieved 2007-09-22.
- ^ "Windows Vista's SuperFetch and ReadyBoost Analyzed". Toms Hardware. 31 January 2007.
- ^ ""Session "ReadyBoot" stopped due to the following error: 0xC0000188" in Windows 7". Microsoft.
- ^ a b Jim Allchin. "Offline Files". Archived from the original on 2007-05-18. Retrieved 2007-06-14.
- ^ Working with network files when you are offline
- ^ Systems Restore in Windows Vista and other backup features
- ^ "Selected Scenarios for Maintaining Data Integrity with Windows Vista". TechNet. Microsoft.
- ^ "Volume Shadow Copy and "Previous Versions" feature in Windows Vista". Microsoft.
- ^ "Managing Roaming User Data Deployment Guide". Archived from the original on 2008-04-05. Retrieved 2010-12-14.