Executive Summary:
Diskeeper 2009 Professional edition, a PC defragmenter geared toward business PC users, offers an improved UI and better configuration options than the built-in defragmenter in Windows Vista. Diskeeper 2009 stands out from similar products because it defragments in the background, without affecting system performance. Weak points of Diskeeper 2009 are some minor bugs in the interface and its confusing messages about performance.

Windows Vista's built-in defragmenter has some serious weaknesses. It barely has a UI, doesn't optimize file placement, takes several passes to defragment a drive effectively, and doesn't really work when a drive has little free space. These weaknesses probably don't affect most computer users, but if they bother you and you want to replace the built-in defragmenter, Diskeeper 2009 Professional is a good choice.

Diskeeper 2009 Professional
PROS: Simple to install; defragments disks without supervision; runs in the background without hurting system performance.
CONS: Some minor bugs in the interface; messages about performance are confusing; performance over the built-in defragmenter might be imperceptible for a typical office system.
RATING: 4 out of 5
PRICE: $59.95 for one machine; volume licensing is available.
RECOMMENDATION: If you've decided you need a disk defragmenter for your desktop other than the built-in Windows defragmenter and you like the idea of continuous defragmenting, Diskeeper 2009 Professional is a good choice.
CONTACT: Diskeeper • (818) 771-1600 • www.diskeeper.com

Diskeeper does its job well. It defragments in the background without hurting system performance, doesn't require defragmentation scheduling, and aside from a few minor bugs, is polished and professional. Diskeeper 2009 Professional edition is geared toward the typical office PC. On my office desktop, I didn't notice a performance improvement, but heavily used machines—especially servers—would probably see greater gains from Diskeeper products. See "3 Enterprise Disk Defragmenters" for more information about Diskeeper's server product.

Using Diskeeper 2009 Professional
Diskeeper's installation took about two minutes and was painless. At this point I could have left Diskeeper alone; after it's installed, Diskeeper starts defragmenting your hard drive in the background. This is one of Diskeeper's best features and one that sets it apart from other defragmenting applications. I never experienced any unusual slowdown when running Diskeeper.

Shortly after installing Diskeeper, I had it analyze my hard drive. After you analyze your drive, you get a colored chart of the disk's files, which Figure 1 shows—something that's missing from Vista's defragmenter.

Diskeeper reported that it detected "moderate fragmentation" on my drive, but on the same screen said my drive was "heavily fragmented." It also reported that by defragmenting the drive, Diskeeper would increase my disk's performance by 1 percent. A 1 percent loss in performance doesn't strike me as heavy or even moderate fragmentation.

Diskeeper also reported that its I-FAAST feature gave me an 18 percent performance gain by sequencing files for better performance. An 18 percent increase in disk performance could be huge on an in-demand server, but it wasn't noticeable on my desktop, as I rarely do anything that requires more than a few seconds of disk access.

Glitches
Diskeeper seems very polished, but after using it a week, I encountered several bugs. Diskeeper either deletes or thoroughly hides the Windows defragmenter Microsoft Management Console (MMC) snap-in, but it doesn't integrate itself into all the places the default defragmenter is integrated. For example, when I clicked Defragment Now in a disk's properties in Windows Explorer, I got an error dialog box stating MMC cannot open the file C:\Progra~1\Diskeeper.

I also experienced a minor bug in the Diskeeper application itself. Every time I started the application, the dashboard displayed a yellow exclamation mark next to drive C and listed its health as Warning. When I clicked recommendations for the drive, Diskeeper reported that Master File Table (MFT) usage on the drive was 98 percent or higher and said to use Diskeeper's Frag Shield feature to automatically configure the MFT. However, I already had enabled Frag Shield. When I opened the Frag Shield options box, then closed it, the drive would be listed as Healthy until I closed the Diskeeper interface and reopened it.

Try It Yourself
If your hard disk has plenty of free space and you mostly use your computer for word processing and email, using Diskeeper 2009 Professional probably won't noticeably improve your system's performance. Even so, the product provides a better UI and more configuration options than the Windows defragmenter. If you want to squeeze every drop of performance out of your system, I recommend you download a free trial of Diskeeper and try it for yourself.