It makes sense that having the files you access most often closest to your hard drive's read-write head will improve your system's performance. Unfortunately, programs tend to store files in various noncontiguous clusters spread across your drive (and occasionally other storage media).
To open or otherwise access a single file, Windows or one of your applications may have to retrieve data from several drive clusters. That's why you need to defragment your hard drive regularly to prevent your system from bogging down.
Windows Vista and Windows 7 claim to defragment your hard disk automatically in the background. The disk-defragmenting utilities built into Vista and Windows 7 are intended to run as a scheduled task: running the utilities manually provides very little feedback as the defragmentation takes place. (Previous versions of Windows used a multicolored graphic to illustrate the progress of the defragger.)
While the Vista defragger offers little more than a warning that the process could take "minutes or hours," Windows 7's manual defragmentation at least indicates the percentage completed.
Get a better view of your drive clusters
In March 2008 I described Auslogics' free Disk Defrag utility, which is most noteworthy for its speed. Many people prefer the free JkDefrag for its simplicity: just double-click the executable and the defrag begins (a GUI version of JkDefrag is also available).
If you're looking for a full-featured disk defragmenter, the $30 Ultimate Defrag from Disktrix provides a wealth of storage-management options, although using the program to defragment a cluttered drive can take hours. (The company previously offered a free version of its defragger. It also sells a $15 version called Defrag Express.)
I tested version 3 of the utility on a relatively pristine 50GB Windows 7 partition and on a badly fragmented 250GB Vista partition, both of which were split about evenly between used and free space. First, I ran the Windows defragger on both machines. When the Vista and Windows 7 defraggers completed, Ultimate Defrag indicated that the Vista partition was still 25.5 percent fragmented and the Windows 7 partition was 8.25 percent fragmented.
Ultimate Defrag took 4 hours and 35 minutes to reduce the Vista fragmentation to about 8.5 percent but couldn't reduce the drive's fragmentation any further. The program pared the Windows 7's partition down to 2 percent fragmentation. On both machines, Auslogics' Disk Defrag and Windows' own defrag utility indicated that the partitions were at or near 0 percent fragmentation.
Digging deeper into disk defragmentation
The first time you open Ultimate Defrag, the program's settings dialog opens and may recommend four presets, one of which disables Windows' scheduled defrags.
Ultimate Defrag lets you select an individual cluster on its disk map and view the files it contains in the left pane. Right-click one of the entries in the left pane to view information about the file, including its folder path, start and end clusters, and links to open it in a folder window or to defragment all the files in that folder.
In addition to the default Consolidation mode, Ultimate Defrag offers modes for fragmented files only, folder/file name, recency, volatility, and "Auto." How the various modes operate isn't clearly explained, although each provides a different set of options. You can list files to exclude from the defragmentation, adjust the performance settings, and choose one of four color schemes.
While it's nice to have this many defrag options, Ultimate Defrag's abundance of features may be overkill for most PC users. If you're looking for total control over your hard drive and other storage media, Ultimate Defrag provides the tools you'll need to get a complete picture of your storage devices. If you simply want to keep your system running smoothly, a freebie such as Auslogics' Disk Defrag may save you more time in the long run.