UltraDefrag speeds up the computer by defragmentation of files.

When files consist of many little fragments scattered around the disk the computer needs more mechanical work to read them. Because of that the disk access becomes slower.

UltraDefrag reduces the file fragmentation, thus it makes disk operations faster. Also the program can optimize a whole disk by placing small files close to each other, sorted by path (or other criteria). After the disk optimization less mechanical work is needed to read groups of small files. This reduces startup times of many applications including web and photo browsers.

In contrast with the most other disk defragmenters UltraDefrag can defragment locked files by running during the Windows boot. Actually all files including page and hibernation files can be defragmented there.

Also UltraDefrag aims to be fast, simple, reliable and efficient.

About the software

UltraDefrag has the following features:

  • system files defragmentation (page-file, hibernation file, ...)
  • MFT (master file table) defragmentation
  • NTFS metafiles defragmentation
  • ultra fast NTFS analysis
  • fast defragmentation algorithm
  • effective disk optimization algorithm (many strategies available)
  • safety, it can never damage processed files
  • simplicity, it can be used without reading the documentation
  • ability to defragment single files/directories from the context menu of Explorer
  • ability to defragment additional streams attached to NTFS files
  • ability to exclude any unimportant files based on flexible filters
  • ability to defragment files, which have more fragments than specified by a threshold
  • ability to automatically break defragmentation when the specified time interval elapses
  • ability to perform defragmentation only when the disk fragmentation level is above the specified value
  • ability to select multiple disks for defragmentation
  • well readable HTML reports
  • powerful command line interface
  • ability to automatically hibernate/shutdown PC after a job is done
  • ability to make an automatic effective defragmentation through Windows Task Scheduler
  • multilingual graphical interface
  • little binaries (about 1 Mb)
  • portable version available which requires no installation
  • native 64-bit support
  • open source code licensed under GPL

UltraDefrag runs on Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008 and Windows 7, including all 64 bit versions of Windows.

UltraDefrag v6 supports Windows NT 4.0 and Windows 2000 as well.

UltraDefrag cannot be used on DOS, Windows 9x, Windows NT 3.51, ReactOS and Mac OS since these operating systems provide no defragmentation API. However, Linux port of UltraDefrag exists. It is based on NTFS-3G capabilities.

Supported file-systems

The following file-systems can be defragmented by UltraDefrag: FAT12/16/32, exFAT and NTFS.

There are a few system restrictions which apply to disk defragmentation. Unfortunately UltraDefrag cannot take away these restrictions:

  • The first clusters of FAT directories cannot be moved. This is a well known FAT driver restriction and cannot be fixed. So, UltraDefrag cannot defragment FAT directories. It tries to optimize them instead by placing all fragments close to each other behind the first one.
  • The first 16 clusters of MFT cannot be moved, this is a file system driver limitation. So, UltraDefrag cannot defragment the MFT. However, it can optimize it by placing all fragments close to each other.

Fragmentation level

The fragmentation level or percentage is calculated as follows:

fragmentation = number of fragmented file fragments / number of all file fragments

Processing algorithms

Defragmentation algorithm

  1. The analysis phase scans the whole disk to collect information about all files and free space.
  2. The defragmentation phase eliminates little fragments by joining them together. This speeds up access to individual files.

Full optimization algorithm

  1. The analysis phase is the same as for defragmentation.
  2. The next phase moves all small files and fragments to the end of the disk to free space at the beginning of it.
  3. The third phase moves small files back, sorted by user defined criteria (by path in ascending order by default). This speeds up access to groups of files.
  4. The last phase defragments all files.

Quick optimization algorithm

Quick optimization consists of the same steps as the full optimization. However, to speed things up it skips already sorted out groups of files. Free space consolidation becomes not so good in this case, but overall disk processing time becomes shorter.

Optimization algorithms ignore any size, name and fragment count filters.

Sometimes even the disk optimization fails to make a large continuous free space gap. This happens when unmovable (locked) files are scattered around the disk. In order to defragment big files (pagefile etc.) in such cases they are two workarounds available:

  • Move all files to another disk, reformat the disk and move all back. This causes the perfect disk optimization.
  • Run GParted or Partition Magic to manually reduce the disk size as much as possible. This operation will move all files including system files to the beginning of the disk. After restoring the original size, you will have a large continuous free space area at the end of the disk. This space may be used hereafter to defragment large files.
UltraDefrag always skips files located directly in MFT records (these files usually have sizes below 1kb), because they are actually part of the MFT. Also files which have no content are skipped, because actually there are no clusters on disk belonging to them. Additionally, UltraDefrag never tries to defragment files marked as temporary by applications which created them. Because such files will be deleted soon, therefore they will not decrease the system performance.

Web resources

Visit UltraDefrag website for more information and news.

For help requests visit our forum.

Please report all problems and bugs via our bug tracker.

To participate in the UltraDefrag translation, please visit the UltraDefrag project at Transifex.

UltraDefrag Wiki is a good place to share some stuff like tutorials and scripts.

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