what is the purpose of disk defragmenter?

Question

for your computer

Answer 1

As you use files and modify them, new parts of a file are stored at a separate location on your disk. It is done this way, so that the whole file does not have to be rewritten each time. This causes the file to be broken up into many pieces (fragmented).

The Defrag program scans your hard drive and moves these parts of the file into a space, so the whole file can be together at the same location. This would make that file open faster. While the performance increase with Windows 2000 and Windows XP is not particularly noticable, it does increase the reliability of the data structure in a long run. I would use DEFRAG about once a week. It does not take very long to run, when it is run often. But use the Disk Cleanup utility first, so you don't waste time defragging files that should be deleted anyway.

Answer 2

Adding and deleting files from your hard disk is a common task. Unfortunately, this process is not always done very efficiently. For example, when you delete a bunch of little files and add a new large file, the file may get broken up into mulitple sections on the hard disk. The computer will still read the newly added file as a single valid file, but the drive will have to scan multiple parts of the disk to read it. Because hard disk seek time is one of the most significant bottlenecks in a computer's performance, this can drag down your computer's speed quite a bit. If you have a ton of "fragmented" files on your hard disk, you might hear extra grinding, sputtering, and other weird noises coming from your computer.

You computer does not like having fragmented files any more than you do. This is why defragmenting your hard disk is such a good idea. When you start to hear extra grinding sounds, or your computer doesn't open files as quickly as it did before, it's time to defragment. With Windows, you can use the pre-installed Intel defragment program to defragment your hard disk. You can also use a commercial software program like Norton Utilities to defragment your hard disk more efficiently and with more options. For Mac users, a disk utility such as DiskWarrior or Tech Tool Pro is the only way to do it. If you use your computer daily, defragmenting your hard drive once a month should keep the fragment-fiends away.

Answer 3

A disk defragmenter moves all the files you have on the disk together so the disk part that reads the files doesn't have to move all around the disk to find all the scattered parts of whatever file needs to be retrieved. The files that are written to the disk are not always put in one piece and can end up scattered all over. I could go into more detail but I hope you get the idea.

Answer 4

As time goes by, files that get written to your hard drive get written in seperate locations on the drive itself. These files are known to be fragmented and the loading of data can be slower than if the files were not fragmented. The disk defragmenter searches the hard disk and places all relevant "chunks" of the file next to each other thus defragmenting the files and also helping speed up the retrieval of data process.

See the wikipedia article for a more indepth explanation

http://en.wikipedia.org/wiki/Defragment

Answer 5

When a program is installed on your computer, the program's files may be broken up over multiple locations on your hard disk. This is called fragmentation. If fragmentation occurs on your hard disk, the performance of programs on your computer is slower. The Disk Defragmenter tool optimizes the performance of your computer by reorganizing the files on your hard disk into contiguous blocks. When the Disk Defragmenter tool completes the defragmentation of files on your hard disk, the performance of your programs is faster because the files are arranged closer together.

Answer 6

whenever you write a file to disk, the computer looks for a new place on the disk to put it. When you delete a file, the space occupied by that file is freed up. If the computer can't find a continuous area of disk to store a file, it will break it up into pieces and scatter them across the disk. Over time, this fragmentation will slow the computer down, as it has to search harder to find places to store files, and conversely, longer to put a chopped up file back together.

The defragmenter undoes all this chaos, restoring split files, consolidating free space into bigger extents, and so on, thus restoring the machine to peak performance.

Answer 7

When new files are downloaded, they are set up in various parts on the drives in the computer, Then when you uninstall anything, most of it goes, but there can be residual pieces. The Disk Defragmenter, cleans up the system. Places all the files in their correct order, so they can be easily opened for use. The unwanted residual pieces can be cleared using Disk Cleanup, but that's another story.

Answer 8

When data gets stored on your hard drive, it doesn't always get stored in a contiguous fashion. As you add and delete data on your hard drive, the data becomes fragmented. The defragmenter, as you can guess, will rearrange the data in a contiguous way so that when your hard drive accesses your files, it does not have to jump from fragment to fragment to read the file. The defragmentation process can thus speed up your computer, modestly, depending on the severity of your initial fragmentation.

Answer 9

Files in the HDD gets fragmented due to various reason i.e. breaks into pieces and gets scattered on the HDD. While accessing it takes time to find them. So defragmenter places the files together for faster access. It's recommended to defragment HDD every month or so depending on your comp usuage. Even installing new software fragments files and frequent power shut downs does the damage too.

Answer 10

In the context of administering computer systems, defragmentation (or defragging) is a process that eliminates fragmentation in file systems. It does this by physically reorganizing the contents of the disk in order to store the pieces of each file close together and in order (contiguously). It also attempts to create large regions of free space using compaction, to impede the return of fragmentation.

Aims of defragmentation
Reading and writing data on a heavily fragmented hard drive is slowed down as the time for the heads to move between fragments on the disk surface can be substantial. The disk operates at speeds millions of times slower than the CPU; thus the desire to process more efficiently encourages defragmentation. Operating system manufacturers often recommend periodic defragmentation in order to keep hard drive access as fast as possible.

Fragmented data also spreads over more of the disk than it needs to. Thus one may defragment in order to compact data storage before splitting a single partition into two or more partitions (for example, with GNU Parted, or PartitionMagic).

Causes and cures
Fragmentation occurs when the operating 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 other files (usually those gaps exist because they formerly held a file that the operating system has subsequently deleted or because the operating system allocated excess space for the file in the first place). As advances in technology bring larger disk drives, the performance loss due to fragmentation squares with each doubling of the size of the drive.[citation needed] Larger files and greater numbers of files also contribute to fragmentation and consequent performance loss. Defragmentation restores a drive to its original speed. It also moves infrequently used files further from the directory area.

A defragmentation program must move files around within the free space available in order to undo fragmentation. This is a memory intensive operation and cannot be performed on a file system with no free space. The reorganization involved in defragmentation does not change logical location of the files (defined as their location within the directory structure).

Another common strategy to optimize defragmentation and to reduce the impact of fragmentation is to partition the hard disk(s) in a way that separates partions of the file system that experience much more reads than writes from the more volatile zones where files are created and deleted frequently. In Microsoft Windows, the contents of directories such as "\Program Files" or "\Windows" are modified far less frequently than they are read. The directories that contain the users' profiles are modified constantly (especially with the Temp directory and Internet Explorer cache creating thousands of files that are deleted in a few days). If files from user profiles were held on a dedicated partiton (as is commonly done on UNIX systems), the defragmenter runs better since it does not need to deal with all the static files from other directories. For partitions with relatively little write activity, defragmentation performance greatly improves after the first defragmentation, since the defragmenter will need to defrag only a small number of new files in the future. Relocating Windows user data onto a dedicated partition is not a trivial task even for experienced users.

Defragmentation issues
The presence of immovable system files (or of files that the defragmenter will not move in order to simplify its task), especially a swap file, can impede defragmentation. ntfsresize can safely move these files in order to resize an NTFS partition.

Certain file systems exhibit a greater susceptibility to fragmentation than others, for example, a FAT file system becomes fragmented much more quickly than NTFS. Many file systems on Unix-like platforms do not require defragmentation at all.[citation needed] These systems attempt to keep fragmentation below a certain point so defragmenting is not necessary. This fragmentation resistance works well as long as the file system has a fairly large amount of space free.

On systems without fragmentation resistance, fragmentation builds upon itself when left unhandled, so periodic defragmentation is necessary to keep disk performance at peak and avoid the excess overhead of less frequent defragmentation.

Utilities
Defragmentation programs often come bundled with an operating system (although Windows NT notably did not include one).

Perhaps the best-known defragmentation utility used to be the MS-DOS and Windows program Defrag. Windows 2000 shipped with a basic edition of Diskeeper, which replaced Defrag (also in name) in the subsequent versions of Windows.

Other commercial defragmentation utilities: PerfectDisk, O&O Defrag and mst Defrag.