I’ve replaced my disk use utility, SequioaView, with a more effective alternative. Like SequoiaView, WinDirStat uses squarified cushon treemaps to provide a graphical representation of file and directory size. Its utility is enhanced by a directory list that is coupled to the treemap display, exposing the relationship between a file or folder’s attributes and its disk space. Additional features include support for network drives, UNC paths, and NTFS junction points. The current version lacks filters, one of SequoiaView’s advantages, however they are being considered for an upcoming release.

Treemaps were developed by Shneiderman and Johnson in the late 1980’s (article here). Instead of showing a file system as a long list of files and directories, treemaps display files as a collection of rectangles with the size of the rectangle being proportional to the size of the file. Cushion Treemaps, invented by Jack van Wijk, enhance the treemap display by adding ridges to the display. The result is a pattern of hierarchical cushions that show the structure in the directories and files.

WinDirStat is an adaption of the KDE program KDirStat (kdirstat.sourceforge.net), which incorporated the treemap features introduced in SequoiaView. SequoiaView was developed based on research done by the Visualization Section of the Faculty of Mathematics and Computer Science at the Technische Universiteit Eindhoven.