And what better way to defrag your brain after a long week than by watching the strangely satisfying defragmentation process taking place on a simulated DOS machine, complete with fan and HDD noise?
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In addition to several programs in the Startup folder, PCs can take their time booting up as antivirus programs run their scans or online file-sharing services update their files, or if the hard drive is overstuffed and in need of defragmentation.
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Starting with file defragmentation in its earlier versions, Auslogics Disk Defrag expanded its capabilities to include free space defragmentation, optimization of file placement based on various criteria, ability to schedule defragmentation, defragment in the background, as well as a number of advanced functions in the professional version of the program.
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PerfectDisk is a defragmentation software product for Windows developed by Raxco. The application keeps track of file usage to lessen defragmentation time and offers two modes of basic defragging: "quick" and "SmartPlacement".
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UltraDefrag is a disk defragmentation utility for Microsoft Windows. Prior to version 8.0.0 it was released under the GNU General Public License. The only other Windows-based defragmentation utility licensed under the GNU GPL was JkDefrag, discontinued in 2008.
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Contig is a command line defragmentation utility for Windows currently owned by Microsoft subsidiary SysInternals.
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In 2018, UltraDefrag sources have been relicensed to Green Gate Systems. Their enhanced 8.0.0 version, released under a proprietary license, features automatic defragmentation and is said to have much faster disk processing algorithms. UltraDefrag uses the defragmentation part of Windows API and works on Windows NT 4.0 and later.
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The now obsolete Commodore Amiga Smart File System (SFS) defragmented itself while the filesystem was in use. The defragmentation process is almost completely stateless (apart from the location it is working on), so that it can be stopped and started instantly. During defragmentation data integrity is ensured for both metadata and normal data.
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There is no online ext3 defragmentation tool that works on the filesystem level. There is an offline ext2 defragmenter, `e2defrag`. However, `e2defrag` may destroy data, depending on the feature bits turned on in the filesystem; it does not know how to handle many of the newer ext3 features. There are userspace defragmentation tools, like ShakeShake. Vleu.net.
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Administrative functions that allow programmatic control over users, databases, and devices, as well as administrative procedures such as backup, defragmentation and consistency checks.
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Edgey # "Overkill" - Terror vs. Enduser # "Champagne Enemaz" - Eighteen Visions vs. Otto Von Schirach # "Zolobovine" - Gorilla Biscuits vs. Defragmentation # "Cannibal Kitten" - The Icarus Line vs.
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UltimateDefrag is a retail file-system defragmentation utility made by DiskTrix. An older version of the program is available as the UltimateDefrag Freeware Edition.
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A command-line tool, defrag.exe, has been included, providing access to the defragmenter from cmd.exe and Task Scheduler. Users who are members of the Power Users group can schedule defragmentation.
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Diskeeper is a defragmentation program designed for Microsoft Windows. It was developed by Executive Software International, Inc., which later changed its name to Diskeeper Corporation, and is now called Condusiv Technologies.
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However, since Windows XP, an increasing number of defragmenters are now able to defragment the MFT, because the Windows defragmentation API has been improved and now supports that move operation. msdn.microsoft.com: "The other big enhancement [in windows XP] is support for online defragmentation of the MFT and most directory and file metadata" Even with the improvements, the first four clusters of the MFT remain unmovable by the Windows defragmentation API, resulting in the fact that some defragmenters will store the MFT in two fragments: The first four clusters wherever they were placed when the disk was formatted, and then the rest of the MFT at the beginning of the disk (or wherever the defragmenter's strategy deems to be the best place).
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The command line utility, Defrag.exe, offers more control over the defragmentation process, such as performing a full defragmentation by consolidating all file fragments regardless of size. This utility can be used to defragment specific volumes or to just analyze volumes as the defragmenter would in Windows XP. Disk Defragmenter is maintained by Microsoft's Core File Services. The Windows Vista version has been updated in Windows Vista SP1 to include the improvements made in Windows Server 2008.
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Windows NT, however, did not offer a Defrag utility, and Symantec was suggested by others as a possible alternative for the utility. Initial releases of Windows NT lacked a defragmentation tool. Versions through Windows NT 3.51 did not have an application programming interface for moving data clusters on hard disks. Executive Software, later renamed Diskeeper Corporation, released Diskeeper defragmentation software for Windows NT 3.51, which shipped with a customized version of the NT kernel and file system drivers that could move clusters.
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Windows 7 reintroduces the analyze function and showing percent complete of the defragmentation, both of which were removed in Windows Vista. It can also defragment multiple volumes simultaneously. According to Scott Hanselman of Microsoft, Windows 7 and later do defragment a solid-state disk (SSD) but in a completely different way. There is less incentive for defragmentation of SSDs because file fragmentation has less performance impact on them and they handle a finite number of storage cycles before their lifespan expires.
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One feature of SFS that is almost unique among Amiga filesystems is its ability to defragment itself while the filesystem is in use, even for locked files. The defragmentation process is almost completely stateless (apart from the location it is working on), which means it can be stopped and started instantly. During defragmentation data integrity is ensured of both meta data and normal data. The filesystem may attempt to move a whole file to a different location when fragmentation is going to occur otherwise.
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Although Windows NT 4.0 introduced an application programming interface (API) for defragmentation, there was no built-in defragmentation utility, unlike Windows 95. Also, Windows NT 4.0 lacked USB support, a preliminary version of which would be added to OEM editions of Windows 95 in OSR 2.1. The difference between the NT family and 9x family would remain until the release of Windows XP in 2001. At that time, the APIs — such as OpenGL and DirectX — had matured sufficiently to be more efficient to write for common PC hardware.
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To defragment a disk, defragmentation software (also known as a "defragmenter") can only move files around within the free space available. This is an intensive operation and cannot be performed on a filesystem with little or no free space. During defragmentation, system performance will be degraded, and it is best to leave the computer alone during the process so that the defragmenter does not get confused by unexpected changes to the filesystem. Depending on the algorithm used it may or may not be advantageous to perform multiple passes.
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Originally, Diskeeper was developed for the VAX series of minicomputers and later for Microsoft Windows. The defragmentation program which is included with Windows 2000, Windows XP and Windows Server 2003 is based on a basic version of Diskeeper.
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Changes in the way Windows operates meant that many of the old utilities were either dropped completely or replaced with GUI based versions. However, with the advent of Windows XP onwards, Norton's Speed Disk reverted to single- cluster defragmentation.
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Defragmentation may decrease lifespan for certain technologies, e.g. solid state drives. Microsoft Drive Optimizer was first officially shipped with Windows XP. From Windows 8, the program was renamed to Microsoft Drive Optimizer, with some references changed to say Defragment and Optimize Drives or simply Optimize Drives.
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A common strategy to optimize defragmentation and to reduce the impact of fragmentation is to partition the hard disk(s) in a way that separates partitions of the file system that experience many more reads than writes from the more volatile zones where files are created and deleted frequently. The directories that contain the users' profiles are modified constantly (especially with the Temp directory and web browser cache creating thousands of files that are deleted in a few days). If files from user profiles are held on a dedicated partition (as is commonly done on UNIX recommended files systems, where it is typically stored in the /var partition), the defragmenter runs better since it does not need to deal with all the static files from other directories. (Alternatively, a defragmenter can be told to simply exclude certain file paths.) For partitions with relatively little write activity, defragmentation time greatly improves after the first defragmentation, since the defragmenter will need to defragment only a small number of new files in the future.
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O&O; Defrag is a Windows defragmentation utility sold by German software developer O&O; Software. It has won several awards by PC journals and magazines, and is certified by Microsoft for all its current NTFS-based operating systems, including Windows 2000, Server 2003, Vista, 7, and 10.
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Defraggler is a freemium defragmentation utility developed by Piriform, which can defragment individual files or groups of files on computer system. Defraggler runs on Microsoft Windows; it has support for all versions since Windows XP. It includes support for both IA-32 and x64 versions of these operating systems.
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While ext3 is resistant to file fragmentation, ext3 can get fragmented over time or for specific usage patterns, like slowly writing large files. Consequently, ext4 (the successor to ext3) has an online filesystem defragmentation utility e4defragExt4 – Linux Kernel Newbies. Kernelnewbies.org (2011-05-19). Retrieved on 2013-06-22.
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The software comes with boot level defragmentation, allowing user-controlled relocation and placement of normally unmovable files, such as the page file. This reduces disk head movement resulting from a page file that is fragmented or located on the hard drive far from other frequently used files. However, the program recommends -- and indeed it is indispensable -- that the user make a backup (which should be a full partition backup, not just data backup) of any drive on which boot level defragmentation is attempted. If the program fails during boot level relocation of critical files such as $MFT, portions of the file structure may be damaged and the computer might no longer boot properly to the desktop screen.
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Vopt (pronounced "vee-opt") is a Windows defragmentation utility sold by Golden Bow Systems."I use the VOPT program from Golden Bow Systems to rearrange the files on my fragmented disks." in Supercharging Windows by Judd Robbins, pg 625 - Sybex 1992 () "A Faster Hard Drive' by Steve Bass, Australian PC World 23 April 2007;Defragment Your Hard Drive in PC Today February 2004, Vol.2 Issue 2 Page(s) 78-80 It is one of the oldest defragmentation products, and has supported MS-DOS and all versions of Microsoft Windows.Chaos Manor Users Choice Awards January 2007: "For about the twentieth year in a row the Chaos Manor Users Choice Award for disk defragmenter goes to Golden Bow's VOPT.
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Microsoft Drive Optimizer (formerly Disk Defragmenter) is a utility in Microsoft Windows designed to increase data access speed by rearranging files stored on a disk to occupy contiguous storage locations, a technique called defragmentation. Defragmenting a disk minimizes head travel, which reduces the time it takes to read files from and write files to the disk. As a result of the decreased read and write times, Microsoft Drive Optimizer decreases system startup times for systems starting from magnetic storage devices such as a hard drive. However, defragmentation cannot be run on storage devices such as solid state drives, USB drives or SD cards that use flash memory to increase speeds, as these drives do not use a head.
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Condusiv Technologies is a software company based in Burbank, California. The company was formerly known as Diskeeper Corporation, a name derived from its flagship product, Diskeeper, a file-system defragmentation software package for Microsoft Windows and OpenVMS. Before adopting the Diskeeper name, the company was known as Executive Software International, Inc.
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When reading data from a conventional electromechanical hard disk drive, the disk controller must first position the head, relatively slowly, to the track where a given fragment resides, and then wait while the disk platter rotates until the fragment reaches the head. A solid-state drive (SSD) is based on flash memory with no moving parts, so random access of a file fragment on flash memory does not suffer this delay, making defragmentation to optimize access speed unnecessary. Furthermore, since flash memory can be written to only a limited number of times before it fails, defragmentation is actually detrimental (except in the mitigation of catastrophic failure). However, Windows still defragments a SSD automatically (albeit less vigorously) to prevent the file system from reaching its maximum fragmentation tolerance.
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The VM supports all Java data types incl. long and double, threads, synchronization, Garbage collection with memory defragmentation, exceptions, system properties and IRQ/event system. The PreonVM comes with a library of driver classes for IO like I2C, SPI, USART, CAN, PWM, IRQ, RTC, GPIO, ADC, DAC and with drivers for some sensors and IC's.
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Individual file fragmentation occurs when a single file has been broken into multiple pieces (called extents on extent-based file systems). While disk file systems attempt to keep individual files contiguous, this is not often possible without significant performance penalties. File system check and defragmentation tools typically only account for file fragmentation in their "fragmentation percentage" statistic.
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Defraggler can defragment individual files, groups of files (in a folder) or an entire disk partition, either by the user's command or automatically on a schedule. It supports FAT32, NTFS, and exFAT. It can also be installed as a portable application on a USB flash drive. Defragmentation of RAID disks is also supported, although no details are supplied.
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Windows 2000's Computer Management console can perform many system tasks. This image shows a disk defragmentation in progress. Windows 2000 introduced the Microsoft Management Console (MMC), which is used to create, save, and open administrative tools. Each of these is called a console, and most allow an administrator to administer other Windows 2000 computers from one centralised computer.
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Database maintenance includes backups, column statistics updates, and defragmentation of data inside the database files. On a heavily used database, the transaction log grows rapidly. Transaction log entries must be removed from the log to make room for future entries. Frequent transaction log backups are smaller, so they interrupt database activity for shorter periods of time.
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The VERITAS File System (or VxFS; called JFS and OnlineJFS in HP-UX) is an extent-based file system. It was originally developed by VERITAS Software. Through an OEM agreement, VxFS is used as the primary filesystem of the HP-UX operating system. With on-line defragmentation and resize support turned on via license, it is known as OnlineJFS.
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Windows 7 and later versions have native support for SSDs. The operating system detects the presence of an SSD and optimizes operation accordingly. For SSD devices Windows disables SuperFetch and ReadyBoost, boot- time and application prefetching operations. Despite the initial statement by Steven Sinofsky before the release of Windows 7, however, defragmentation is not disabled, even though its behavior on SSDs differs.
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File system utilities which require dedicated access can be effectively completed piecemeal. In addition, defragmentation may be more effective. Several system maintenance utilities, such as virus scans and backups, can also be processed in segments. For example, it is not necessary to backup the file system containing videos along with all the other files if none have been added since the last backup.
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AddStor, Inc. offered an add-on product called Double Tools for DoubleSpace. It contained a number of tools to enhance the functions of the version of DoubleSpace that came with MS-DOS 6.0. This included various diagnostic features, the ability to have compressed removable media auto-mounted as they were used, as well as support for background defragmentation of DoubleSpace compressed drives.
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Defragmentation, shrinking and rebalancing operations require extents to be relocated. However, doing a simple copy-on- write of the relocating extent will break sharing between snapshots and consume disk space. To preserve sharing, an update-and-swap algorithm is used, with a special relocation tree serving as scratch space for affected metadata. The extent to be relocated is first copied to its destination.
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DBMS use statistic histograms to find data in a range against a table or index. Statistics updates should be scheduled frequently and sample as much of the underlying data as possible. Accurate and updated statistics allow query engines to make good decisions about execution plans, as well as efficiently locate data. Defragmentation of table and index data increases efficiency in accessing data.
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Defragmentation is advantageous and relevant to file systems on electromechanical disk drives (hard disk drives, floppy disk drives and optical disk media). The movement of the hard drive's read/write heads over different areas of the disk when accessing fragmented files is slower, compared to accessing the entire contents of a non-fragmented file sequentially without moving the read/write heads to seek other fragments.
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The 1.0 and 1.1 Java virtual machines (JVMs) used a mark-sweep collector, which could fragment the heap after a garbage collection. Starting with Java 1.2, the JVMs changed to a generational collector, which has a much better defragmentation behaviour.IBM DeveloperWorks Library Modern JVMs use a variety of methods that have further improved garbage collection performance.For example, the duration of pauses is less noticeable now.
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The presence of immovable system files, especially a swap file, can impede defragmentation. These files can be safely moved when the operating system is not in use. For example, ntfsresize moves these files to resize an NTFS partition. The tool PageDefrag could defragment Windows system files such as the swap file and the files that store the Windows registry by running at boot time before the GUI is loaded.
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The correction to existing fragmentation is to reorganize files and free space back into contiguous areas, a process called defragmentation. In modern computers, with SSD "disks" that do not rotate and are not really discs in the conventional sense, file system fragmentation is not as much of a performance problem (that should be "fixed"), as there is no movement of heads or discs. In fact, overly defragmenting such drives can slowly shorten their lifespan.
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The filesystem is reasonably good at keeping files unfragmented, although there is a defragmentation tool available which will work on an online filesystem. It was the first filesystem to introduce the concept of the Recycle Bin natively at filesystem-level to the Amiga, holding the last few deleted files in a hidden directory on the disk root. PFS version 5.3 was developed in C and a small portion of assembly code by Michiel Pelt.
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Btrfs also has "a number of the same design ideas that reiser3/4 had". Btrfs 1.0, with finalized on-disk format, was originally slated for a late-2008 release, and was finally accepted into the Linux kernel mainline in 2009. Several Linux distributions began offering Btrfs as an experimental choice of root file system during installation. In July 2011, Btrfs automatic defragmentation and scrubbing features were merged into version 3.0 of the Linux kernel mainline.
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Symantec Utilities for Macintosh (SUM) was a set of system utilities from Symantec, developed before Symantec had acquired Peter Norton Computing. SUM started out as a revised version of the MacZap data recovery tools and included utilities for data recovery, disk partitioning, disk defragmentation, and floppy disk duplication, among others. Later SUM tools may have shared code with Norton Utilities for Macintosh. Some of the functionality from SUM II was incorporated into Norton Utilities 2.0.
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As mentioned above, RC uses a hybrid of regions and reference counting, limiting the overhead of reference counting since references internal to regions don't require counts to be updated when they're modified. Similarly, some mark-region hybrid methods combine tracing garbage collection with regions; these function by dividing the heap into regions, performing a mark-sweep pass in which any regions containing live objects are marked, and then freeing any unmarked regions. These require continual defragmentation to remain effective.
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A Norwegian Environment Agency review report about microplastics published in early 2015Sundt, Peter and Schulze, Per-Erik: "Sources of microplastic- pollution to the marine environment", "Mepex for the Norwegian Environment Agency", 2015 states it would be beneficial to classify these sources as primary, as long as microplastics from these sources are added from human society at the "start of the pipe", and their emissions are inherently a result of human material and product use and not secondary defragmentation in nature.
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IFS and helpers remain as the same, but later, in Windows NT 4.0, a defragmentation helper (DEFRAG) was added. Microsoft's original NTLDR was coded for loading the NT kernel from FAT, HPFS or NTFS, but subsequent versions dropped HPFS support. All of the drivers and helpers became 32-bit PE executables. The FAT file system was moved out of the Kernel to an IFS and was heavily optimized for performance, taking advantage of the 32-bit processing capabilities (being called FASTFAT).
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Without support for TRIM, the SSD would be unaware of this data being invalid and would unnecessarily continue to rewrite it during garbage collection causing further wear on the SSD. It is beneficial to make some changes that prevent SSDs from being treated more like HDDs, for example cancelling defragmentation, not filling them to more than about 75% of capacity, not storing frequently written-to files such as log and temporary files on them if a hard drive is available, and enabling the TRIM process.
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The helpers only inspect one packet at a time, so if vital information for connection tracking is split across two packets, either due to IP fragmentation or TCP segmentation, the helper will not necessarily recognize patterns and therefore not perform its operation. IP fragmentation is dealt with the connection tracking subsystem requiring defragmentation, though TCP segmentation is not handled. In case of FTP, segmentation is deemed not to happen "near" a command like `PASV` with standard segment sizes, so is not dealt with in Netfilter either.
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The reorganization involved in defragmentation does not change logical location of the files (defined as their location within the directory structure). Besides defragmenting program files, the defragmenting tool can also reduce the time it takes to load programs and open files. For example, the Windows 9x defragmenter included the Intel Application Launch Accelerator which optimized programs on the disk by placing the defragmented program files and their dependencies next to each other, in the order in which the program loads them, to load these programs faster.Cwdixon.com . Cwdixon.com.
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Skyguide is a member of Functional Airspace Block Europe Central (FABEC)[6], which controls some 55% of all the air traffic handled in Europe, or around 5.3 million flights a year. The six FABEC member states – Belgium, France, Germany, Luxembourg, the Netherlands and Switzerland – signed the corresponding international agreement in December 2010, laying the legal foundation for the new airspace entity. Skyguide's main contribution to the defragmentation of European airspace, however, is its concept to consolidate existing air navigation centres into a virtual entity (the "Virtual Centre").
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Because of this, XFS enables extreme scalability of I/O threads, file system bandwidth, and size of files and of the file system itself when spanning multiple physical storage devices. XFS ensures the consistency of data by employing metadata journaling and supporting write barriers. Space allocation is performed via extents with data structures stored in B+ trees, improving the overall performance of the file system, especially when handling large files. Delayed allocation assists in the prevention of file system fragmentation; online defragmentation is also supported.
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The appeal court, thus, agreed with the district court that Philips failed to establish a genuine issue of material fact regarding direct infringement for all but the four models with corresponding customer service records. The court decided Philip's notices of infringement provided Netgear sufficient knowledge of infringement. Likewise, the court could not find substantial non-infringing uses of wireless fragmentation. When considering material part of invention, the district court claimed defragmentation did not infringe US patent 4,974,952 as it only made material claims of fragmentation techniques.
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Retroactive techniques attempt to reduce fragmentation, or the negative effects of fragmentation, after it has occurred. Many file systems provide defragmentation tools, which attempt to reorder fragments of files, and sometimes also decrease their scattering (i.e. improve their contiguity, or locality of reference) by keeping either smaller files in directories, or directory trees, or even file sequences close to each other on the disk. The HFS Plus file system transparently defragments files that are less than 20 MiB in size and are broken into 8 or more fragments, when the file is being opened.
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Defragmentation is the operation of moving file extents (physical allocation blocks) so they eventually merge, preferably into one. Doing so usually require at least two copy operations: one to move the blocks into some free scratch space on the disk so more movement can happen, and another to finally move the blocks into their intended place. In such a paradigm, no data is ever removed from the disk, so that the operation can be safely stopped even in the event of a power loss. The article picture depicts an example.
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Some file systems defer operations such as reorganization of free space, secure erasing of free space, and rebuilding of hierarchical structures by providing utilities to perform these functions at times of minimal activity. An example is the file system defragmentation utilities. Some of the most important features of file system utilities involve supervisory activities which may involve bypassing ownership or direct access to the underlying device. These include high-performance backup and recovery, data replication and reorganization of various data structures and allocation tables within the file system.
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These formats support file fragmentation (with the so-called "new map"), storage of multiple files per fragment and storage of small files in directory tables. The allocation strategy is optimised to minimise fragmentation, and sometimes performs defragmentation as part of a file storage operation. RISC OS 4 added E+/F+ format which allowed for long filenames and more than 77 files per directory. More recent versions of RISC OS, including those for Iyonix, continue to provide ADFS, and have further extended it to cope with larger hard disc sizes.
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Peter A. Franaszek is an American information theorist, an IEEE Fellow, a research staff member emeritus at the IBM T.J. Watson Research Center and a former member of the IBM Academy of Technology. He received his Sc.B. from Brown University in 1962, and his Ph.D. from Princeton University in 1966. His work was mainly on the representation of information for storage and transmission, and the placement and movement of such information in computer systems. Specific areas include constrained coding, compression algorithms, I/O architectures, switching networks, disk defragmentation algorithms, concurrency control techniques, operating system schedulers, and compression techniques and architectures for systems with memory compression.
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On spinning HDDs this does not adversely affect files that are sequentially written, randomly read, or are subsequently read using the same temporal pattern, but does affect sequential read after random write spatial data access patterns because of magnetic head could be only in one position at a time to read data from platter while fragmentation does no effect on SSD drives. Releases of ONTAP since 7.3.1 have included a number of techniques to optimize spatial data layout such as the reallocate command to perform scheduled and manual defragmentation, and the Write after Reading volume option which detects and automatically corrects suboptimal data access patterns caused by spatial fragmentation. Releases of ONTAP 8.1.
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Information regarding files is displayed in a circular graph representing the physical disk, indicating sections that are fragmented, compressed, reserved for system use, along with other information. From this, the user can select sections of the disk, see a list of the files in that section showing information regarding individual file fragmentation and location, and individually defragment files or drag and drop them to the desired section on the disk. Along with defragmentation, UltimateDefrag performs consolidation of both disk space and files within folders, arrangement of files by volatility (most often used files) or recency (most recently used files), and analysis of the disk. In addition, UltimateDefrag has the ability to defragment files based on manually entered wildcard expressions.
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If supported by the SSD (not implemented on early devices), this optimizes when erase cycles are performed, reducing the need to erase blocks before each write and increasing write performance. Several tools and techniques that were implemented in the past to reduce the impact of the rotational latency of traditional HDDs, most notably disk defragmentation, SuperFetch, ReadyBoost, and application launch prefetching, involve reorganizing (rewriting) the data on the platters. Since SSDs have no moving platters, this reorganization has no advantages, and may instead shorten the life of the solid state memory. Therefore, these tools are by default disabled on SSDs in Windows 7, except for some early generation SSDs that might still benefit.
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Fragmentation occurs when the file system cannot or will not allocate enough contiguous space to store a complete file as a unit, but instead puts parts of it in gaps between existing files (usually those gaps exist because they formerly held a file that the file system has subsequently deleted or because the file system allocated excess space for the file in the first place). Files that are often appended to (as with log files) as well as the frequent adding and deleting of files (as with emails and web browser cache), larger files (as with videos) and greater numbers of files contribute to fragmentation and consequent performance loss. Defragmentation attempts to alleviate these problems.
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However, modern systems profit enormously from the huge disk capacities currently available, since partially filled disks fragment much less than full disks, and on a high-capacity HDD, the same partition occupies a smaller range of cylinders, resulting in faster seeks. However, the average access time can never be lower than a half rotation of the platters, and platter rotation (measured in rpm) is the speed characteristic of HDDs which has experienced the slowest growth over the decades (compared to data transfer rate and seek time), so minimizing the number of seeks remains beneficial in most storage-heavy applications. Defragmentation is just that: ensuring that there is at most one seek per file, counting only the seeks to non-adjacent tracks.
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PlayStation Broadband Navigator, PlayOnline Viewer, Pop'n Music Puzzle-dama Online) are keyed to the system when that system installs them. The HDD can be transferred to another PlayStation 2 system and files on the HDD can be accessed, but those specific programs cannot be booted without being reinstalled. Contrary to popular belief, a complete reformat of the HDD is not necessary upon transfer of the HDD between consoles, or else it would not be useful to have the HDD be preformatted and have preinstalled software, as is the case with the North American HDD unit. An HDD Utility Disc is included to allow maintenance of the HDD (including defragmentation, disk repair and formatting utilities, along with a file manager browser) and in North America, Final Fantasy XI is also included.
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April EDW (built on April 19, 2006 with a build number of 5365), which was released on April 21, 2006, introduced more changes to visual user interface elements, and to the behavior of User Account Control. A number of new backgrounds were also introduced, and two new screensavers were added as well. The Sidebar was enabled by default, as was automatic defragmentation of the hard drive. Hold'em, a game that shipped with some previous CTPs, was dropped due to apparent "political sensitivity" issues; Microsoft now offers it as a separate web download for Windows Vista Ultimate users. Windows Vista Beta 2 Preview (built on May 1, 2006, with a build number of 5381) was leaked on May 2, 2006, and was officially released on May 6, 2006, to Microsoft's technical beta testers.
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Some of the features, including the background defragmentation capability, required the user to let Double Tools replace the standard compression driver for MS-DOS (DBLSPACE.BIN) with one developed by Addstor, claimed to be 100% compatible with DoubleSpace and the Microsoft Real-Time Compression Interface introduced in MS-DOS 6.0. This driver added a number of extra features, such as the use of 32-bit code paths when it detected an Intel 80386 or higher CPU, caching capabilities and - in addition to its supporting the use of the Upper Memory Area - also permitted the use of Extended Memory for some of its buffers (reducing the driver's total footprint in conventional and upper memory, albeit at the cost of somewhat reduced speed). Other features provided by Double Tools was the ability to have compressed removable media auto-mounted as they were used (instead of the user having to do this manually).
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In Windows Vista, Disk Defragmenter includes an option to automatically run at scheduled times using Task Scheduler and uses low CPU priority and the newly introduced low priority I/O algorithm so that it can continue to defrag using reduced resources (less CPU and disk read/write activity) when the computer is in use. The user interface has been simplified, with the color graph, progress indicator, disk analysis and fragmentation information being removed entirely. If the fragments of a file are over 64 MB in size, the file is not defragmented if using the GUI; Microsoft has stated that this is because there is no discernible performance benefit since the time seeking such large chunks of data is negligible compared to the time required to read them.Disk Defragmenter FAQs The result, however, is that Disk Defragmenter does not require a certain amount of free space in order to successfully defrag a volume, unlike performing a full defragmentation which requires at least 15% of free space on the volume.
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