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To reorganize the disk by putting files into contiguous order. Because the operating system stores new data in whatever free space is available, data files become spread out across the disk as they are updated. Large files may be broken into thousands of fragments, causing the read/write head to move back and forth numerous extra times to read the data. A "defragger" or "optimizer program" rewrites all the files and stores them in adjacent sectors.

Windows comes with the DEFRAG.EXE utility, which can be activated by the Run dialog from the Start menu. Other popular defraggers, such as Diskeeper, offer enhanced capabilities.

Users Run the Gamut
Some users are fanatical about defragging their disks on a regular basis. Others rarely do it, if ever. After defragmenting, performance increases are most noticeable on very large databases that had been heavily fragmented. Because today's computers are so fast, users may not notice any increase in speed with routine applications such as word processing and spreadsheets, especially if the files are small.

A Good Habit
Nevertheless, defragmenting disks regularly is good practice because it reduces wear and tear on the drive mechanism. In addition, should the hard disk ever crash and you did not back up important files, data recovery experts will tell you that a defragged disk is much easier to restore.

Before and After
This Diskeeper example shows the fragmented files (in red) before defragging and the results below. Diskeeper can be set up to defrag the disk whenever the machine is idle. As soon as the user clicks the mouse or presses a key, the defragging is suspended.
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References in periodicals archive ?
The bottom line is that while you could defrag your disk without this software, you probably won't remember to do so all that often, and that could result in degraded systems performance.
"Defrag Manager has always been an important component of Winternals' strategy to help our customers achieve a highly optimized Windows enterprise and the greatest possible return on their Microsoft infrastructure," said Edwin Brasch, president and CEO of Winternals.
If you don't get the defrag results you need, or you want an automated, powerful solution, I recommend Diskeeper 7.
They include: (1) the inability to use disk caching routines such as SmartDrive, which really slows disk access; (2) much slower disk defragmenting - over an hour to defrag a compacted disk vs.
Defrag (optimize storage space with a program such as Norton Utilities) your hard drive to eliminate any errors.
Disk utilities such as the MS-DOS command defrag will rewrite the data with no holes or fragments.
Chapel Hill, NC, October 05, 2016 --( ApexSQL, a Microsoft Gold Certified Partner and a major provider of Microsoft SQL Server solutions, announced the release of a new product - ApexSQL Defrag 2016.
Think of your brain as a computer that needs to defrag. A busy mind is scattered.
Odds and ends discovered while running the defrag program on the old laptop:
Secondly, the tiny Defraggler provides the 'quick defrag' option, which reduces the lengthy defragmentation process by selectively defragging files.
You mush (defrag) all the grapes (Word files and stuff) together, creating more space (memory) in the bucket.