ext3, or third extended filesystem, is a journaled file system that is commonly used by the Linux kernel. It used to be the default file system for many popular Linux distributions. Stephen Tweedie first revealed that he was working on extending ext2 in Journaling the Linux ext2fs Filesystem in a 1998 paper, and later in a February 1999 kernel mailing list posting. The filesystem was merged with the mainline Linux kernel in November 2001 from 2.4.15 onward. Its main advantage over ext2 is journaling, which improves reliability and eliminates the need to check the file system after an unclean shutdown. Its successor is ext4.
Windows 98 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. The second operating system in the 9x line, it is the successor to Windows 95, and was released to manufacturing on May 15, 1998, and generally to retail on June 25, 1998. Like its predecessor, it is a hybrid 16-bit and 32-bit monolithic product with the boot stage based on MS-DOS.
In the maintenance of file systems, defragmentation is a process that reduces the degree of fragmentation. It does this by physically organizing the contents of the mass storage device used to store files into the smallest number of contiguous regions. It also attempts to create larger regions of free space using compaction to impede the return of fragmentation. Some defragmentation utilities try to keep smaller files within a single directory together, as they are often accessed in sequence.
Norton Utilities is a utility software suite designed to help analyze, configure, optimize and maintain a computer. The latest version of the original series of Norton Utilities is Norton Utilities 16 for Windows XP/Vista/7/8 was released 26 October 2012.
PageDefrag is a program, developed by Sysinternals, for Microsoft Windows that runs at start-up to defragment the virtual memory page file, the registry files and the Event Viewer's logs.
PC Tools is a collection of software utilities for DOS developed by Central Point Software.
Diskeeper is a discontinued defragmentation app, 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. The final version of Diskeeper was released in March 2020. All of Diskeeper's features and functionality are now included in Condusiv's data performance software DymaxIO.
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 accomplishes this by caching files that are needed by an application to RAM as the application is launched, thus consolidating disk reads and reducing disk seeks. This feature was covered by US patent 6,633,968.
Microsoft Drive Optimizer 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 is not helpful 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. Defragmentation may decrease lifespan for certain technologies, e.g. solid state drives. Microsoft Drive Optimizer was first officially shipped with Windows XP.
Contig is a command line defragmentation utility for Windows developed by Microsoft as part of the Sysinternals Suite.
Windows Vista contains a range of new technologies and features that are intended to help network administrators and power users better manage their systems. Notable changes include a complete replacement of both the Windows Setup and the Windows startup processes, completely rewritten deployment mechanisms, new diagnostic and health monitoring tools such as random access memory diagnostic program, support for per-application Remote Desktop sessions, a completely new Task Scheduler, and a range of new Group Policy settings covering many of the features new to Windows Vista. Subsystem for UNIX Applications, which provides a POSIX-compatible environment is also introduced.
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.
Defraggler is a freemium defragmentation utility developed by Piriform Software, which can defragment individual files or groups of files on computer memory systems. 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.
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.
WorldBench is a Windows benchmark tool offered by PC World Labs since 2000. The PC World Test Center uses this same tool every month to test contenders for PC World's Top Desktop PCs and Top Notebook PCs charts. WorldBench is also used in conjunction with other tests to evaluate Top Graphics Boards, Top Hard Drives, and other product categories.
JkDefrag is a free open-source disk defragmenting utility computer program for Windows. It was developed by Jeroen Kessels beginning in 2004 and was released under the GNU General Public License. Since version 4 of 2008, much changed from previous versions, JkDefrag was renamed MyDefrag by its developer; earlier JkDefrag versions continued to be available. MyDefrag, which was closed source freeware, was discontinued, with the last version being v4.3.1, file date 21 May 2010; for several years the MyDefrag website has been a redirect to the still-existing JkDefrag site, but links to downloadable JKdefrag files are dead.
AVG TuneUp, previously called AVG PC Tuneup, and TuneUp Utilities, is a utility software suite for Microsoft Windows designed to help manage, maintain, optimize, configure, and troubleshoot a computer system. It was produced and developed by TuneUp Software GmbH. TuneUp Software was headquartered in Darmstadt, Germany, and co-founded by Tibor Schiemann and Christoph Laumann in 1997. In 2011, AVG Technologies acquired TuneUp Software. AVG was then acquired by Avast in 2016 and became a part of larger company Gen Digital in 2022.
The following is a comparison of notable file system defragmentation software:
Auslogics Disk Defrag is a freemium software application for Microsoft Windows intended to defragment files and folders on a hard drive, consolidate free space and optimize file placement using different criteria. It has an estimated 10 It is available in both free and "Pro" versions.
PerfectDisk is a defragmentation software product for Windows developed by Raxco.
