Contig (defragmentation utility)
|Developer(s)||Mark Russinovich, Sysinternals|
|Stable release||1.7 / Nov 15 2012|
Contig is designed to defragment individual files, or specified groups of files, and does not attempt to move files to the beginning of the partition. Unlike the Windows built-in defragmenter tool, Contig can defragment individual files, individual directories, and subsets of the file system using wildcards.
Contig does not move any data except that belonging to the file in the question, so the amount it can defragment a file is limited to the largest contiguous block of free space on a system. Use of contig exchanges decreases file fragmentation for increased free space fragmentation.
Combined usage of the -s parameter and the wildcard symbol * allows whole directories and drives to be defragmented: for example,
contig -s C:\*
will defrag all the files on hard drive C. The -s parameters means to browse directories recursively. Directories, for example, can be defragmented with the following command. This will help speed up accessing files in a directory with many hundreds or thousands of files.
for /R /D %a in (*.*) do start /b contig -q "%a" > nul
Adding the -v parameter to the command runs contig in verbose mode.
contig -v -s C:\*
When the filesystem is NTFS, contig can also analyse and defragment the following files:
$mft, $LogFile, $Volume, $Attrdef, $Bitmap, $Boot, $BadClus, $Secure, $UpCase, $Extend
This feature is undocumented on Microsoft TechNet's site, but contig displays this information when run this way:
contig -v -s C:\
without the * character after the drive name. (At least this works when running contig from an external drive.)
contig -v -s $mft
A small change to the Windows registry allows entire folders to be defragmented from Windows Explorer. New unfragmented files with specified name and length can be created.
Derivative programs that use Contig include Power Defragmenter GUI and Multiple Applicator 6.8. A related freeware product by the same author is PageDefrag.
- Contig can't defragment files accessed through directory mount points (as opposed to drive letter mounts). Using an additional (temporary) drive letter will circumvent this problem. See subst command.
- Contig doesn't work in Telnet sessions, but it is possible to execute it on remote machines using Sysinternals PsExec.
- Comparison of defragmentation software
- File system fragmentation
- List of defragmentation software
Notes and references
- Windows NT Magazine column, "Inside the Object Manager" October 1997
- Documentation on TechNet page
- Edwards, Donn (31 August 2007). "Make Contig Easier to Use". Insights and Rants. Retrieved 19 May 2010. "
@="Defragment Folder using contig"
@="cmd.exe /K contig.exe \"%L\" -v -s"