Executive Summary: This comparison of three disk defragmentors--Diskeeper’s Diskeeper 2008 Server, O&O Software’s O&O Defrag 10 Server Edition, and Raxco’s PerfectDisk 2008 Server--will help you determine the best product for your environment.

Monitors are getting thinner, CPUs are becoming faster, and software is getting easier to use. But one aspect of computing that remains the same is hard disk fragmentation. Our OSs—for various reasons— are failing to store files in contiguous disk space and are instead tossing parts here and there, filling in disk gaps willy-nilly. Our poor hard disks have to read portions of files scattered all over the platter, rather than reading files in smooth, continuous motions.

So, you need a defragmentation tool. Where do you start? We’ve selected three products for a comparative review—Diskeeper’s Diskeeper 2008 Server, O&O Software’s O&O Defrag 10 Server Edition, and Raxco’s PerfectDisk 2008 Server—that should help you decide which best suits your environment.

All three companies also offer workstation editions (and even products for Exchange Server, SQL Server, and Windows Home Server), but I found few differences between these server and workstation versions. The primary goal of both is to simply defragment a computer’s hard disk. However, the server versions in this review either come with built-in enterprise functionality or offer a separate add-on to help you centrally manage your defragmentation tasks.

Testing
To permit straightforward comparison of the products’ features, I used VMware Server 1.0.4 to install each product on a virtual machine (VM). However, I also felt it was important to install each product on actual hardware to compare performance results, so I did that, too. To ensure that I compared the products fairly, I used disk-imaging software to capture a heavily fragmented hard disk with only 20 percent free space. In addition, I included one extremely fragmented file that was larger than the free space, as well as one heavily fragmented disk with a lot of free space. In just a few minutes, I could easily reproduce the fragmented drives for testing. Then, I used each product to run one manual defrag pass on the hard disk. You can find the results in Table 1.

Product Overview
All three products offer offline and online defragmentation. Offline defragmentation occurs on files that are in use while the OS is running. Files that can be defragmented only while the OS isn’t running include the Master File Table (MFT), the hibernation file, and the paging file. Only Diskeeper and PerfectDisk let you schedule an offline defrag.

The products differ in their online defrag approach—that is, defragmenting files while the system is running. Both PerfectDisk and O&O Defrag take a scheduled defrag approach, and they both have wizards to help you automate the scheduling process. Diskeeper constantly runs in the background.

If you need to deploy and manage defrags on multiple systems from one central location, take a close look at each product’s functionality in this area, because each one offers something different. O&O Defrag includes a Network Management tool (with the Server edition), Diskeeper offers an add-on product called Diskeeper Administrator, and Perfect- Disk (as of this writing) is working on a new product called Command Center. (According to the company Web site, Command Center will be available to PerfectDisk 2008 customers at no additional charge.)

PerfectDisk and Diskeeper both work with Microsoft Volume Shadow Copy Service (VSS). When a disk defragmenter moves enough data around the disk, VSS can mistakenly assume that a file change has occurred, and thus take a snapshot. Both of these products let you to make the system “VSS aware” so that unnecessary snapshots don’t occur.

Diskeeper
I started the application by double-clicking the desktop icon. The opening screen is immediately overwhelming, particularly compared with the GUIs of the other two products. Instead of easy-to-read labels, Diskeeper has cryptic icons that you must “hover” your mouse over to see what they do. Perhaps I’m being picky, but my initial impression was that the other two products offer much simpler interfaces. On a brighter note, a Quick Start Guide in the interface’s left pane helps get you started in the right direction. Figure 1 shows the Diskeeper interface.

Defragmenting. Diskeeper is unique in that it offers not only classic online and offline defragmentation that you can set manually and schedule, but also a new method called Automatic Defragmentation (which debuted in Diskeeper 2007). Automatic Defragmentation runs silently in the background to ensure that all your hard disks stay defragmented. My first concern was that this feature would consume valuable resources from the server. But Diskeeper uses InvisiTasking technology to monitor disk I/O, memory allocation, and CPU usage to ensure that Diskeeper never negatively affects your users. Automatic Defragmentation will even choose the appropriate engine to use, depending on the kind of fragmentation you have (e.g., heavy fragmentation, low free disk space).

Letting disk-defragmenter software run in the background and configure itself is a new concept to most administrators. Offline and online manual defragmentation is available, but it isn’t necessary to run; you can just install it and have a nice day.

Above and beyond. What sets Diskeeper apart from the other two products is the Automatic Defragmentation feature, ensuring that your systems are always in an un-fragmented state. Another interesting feature is Intelligent File Access Acceleration Sequencing Technology (I-FAAST). This feature, according to Diskeeper, sequences files to take best advantage of the logical and physical characteristics of a volume. In short, Diskeeper orders data on the disk so that the content you use most often can be retrieved faster.

O&O Defrag
The installation of O&O Defrag proceeded without a hitch. One interesting feature of the installation routine is its Register O&O Defrag as the standard defrag tool check box. By contrast, PerfectDisk doesn’t replace the default, built-in defragmentation tool that comes with Windows, and Diskeeper replaces it without asking. O&O Defrag gives you a choice.

After installation, O&O Defrag immediately started a wizard to help set up OneButtonDefrag (which Figure 2 shows), a feature that promised to “automate defragmentation with just a few mouse clicks.” Opening the other products, I felt unsure where to begin; O&O Defrag got me started quickly on the right foot. I chose to use the wizard, selected Server (from a choice between Desktop, Laptop, or Server), and then File Server (from a choice between File Server, Database Server, Web Server, or Mail Server).

Next, I used the Check for Updates tool in the Help ribbon. The version I’d installed was the most up-to-date version, but this was a great feature that the competing vendors in this category would do well to consider.

Defragmenting. For online defrags, O&O Defrag uses a technology called ActivityGuard that monitors your CPU usage. When you’re performing CPU-intensive activities during a scheduled defrag, O&O Defrag uses less of your CPU. But when the processor is idle, O&O Defrag takes the opportunity to optimize more files. You can further tone ActivityGuard to use all available resources or a percentage of the CPU that you specify. In addition, you can set O&O Defrag to defrag each physical drive simultaneously or sequentially. You might choose simultaneous defrags if you need to quickly defrag all of a server’s disks. Defragging sequentially takes more time but saves valuable system resources.

Continue to Page 2

Offline defragmentation occurs at boot time. It’s disabled by default, so you have to specifically set it by clicking Settings and accessing the Offline Defragmentation tab. You can set the tool to defrag at every startup or on just the next startup. The defragmentation occurs right after a Chkdsk.

OneButtonDefrag is a great way to quickly set up online defragmentation. O&O Defrag sets up the schedule and all the options for you. But if you want more control of how your system optimizes its files, you can set everything manually. Adding your own job in this way reveals many of the advanced features that OneButtonDefrag takes care of for you. There are five available defragmentation methods that you can choose from (i.e., Stealth, Space, Complete-Access, Complete- Modified, Complete-Name), depending on the available resources of the server, the amount of files and free space on the hard disk, and the system’s primary use. For example, the Complete-Access method places recently used files at the beginning of the partition, thereby reducing access time.

The two remaining tabs are for scheduling scripts to run either before or after a scheduled defrag. According to the user manual, the scripting feature can be useful for shutting down applications such as Exchange Server or SQL Server before a defrag run, then starting these services back up again.

Above and beyond. O&O Defrag has the simplest interface of all three products (the PerfectDisk coming in a close second). The OneButtonDefrag wizard helps you ensure that you set up your defrag schedule correctly the first time.

If I have one complaint, it’s that O&O’s support is lacking. The only number on the O&O Web site is German, and I couldn’t get through after repeated attempts. The support Web site doesn’t offer much information, either. For example, O&O Defrag has provisions to run CMD scripts before and after a scheduled defrag. I’m familiar with writing CMD scripts to shut down and restart NT services, but some administrators might not know where to start. The addition of a knowledge base to discuss this kind of problem would be a great benefit.

PerfectDisk
Like the other two products, PerfectDisk boasts a simple setup routine, asking basic questions and proceeding smoothly. The PerfectDisk installer comes in an MSI format suitable for deployment via your favorite method (e.g., Group Policy, Microsoft Systems Management Server—SMS). Perfect- Disk is also written to be controlled through a Group Policy Administrative Template (ADM). So, not only can you deploy the application to your other servers and workstations, but you can control what those users can do with PerfectDisk.

I started the application by double-clicking the desktop icon. Doing so brought up the main PerfectDisk window.

Defragmenting. When I first started PerfectDisk, I needed a little direction. I perused the user guide on the CD-ROM and checked out the company Web site, but I got better information when I contacted tech support. A friendly technician directed me to a knowledge base article titled “How Often Should I Defragment My System?” This brief article suggested performing a drive analysis to see what kind of defrag PerfectDisk recommends.

This analysis took only a few minutes, and at the end, a Start button appeared in the screen’s lower right corner, as you see in Figure 3. Clicking this button brought up a cryptic dialog box that read, Offline defrag of your System Files could not run on drive C: because the drive is in use by another process. Do you want to force all open handles closed? Like the other products in this review, PerfectDisk can’t defrag system files such as the paging file and MFT because they’re in use. I expected PerfectDisk to ask me whether I wanted to schedule a defrag at system reboot, but strangely, PerfectDisk attempted to close those system files, then prompted me to reboot the system so that the offline defrag could proceed.

After the reboot, I returned to the Analyze screen and PerfectDisk prompted me to analyze the disk again. I did so, then clicked the Start button, and an online defrag started immediately. According to the technician that I talked to on the phone, running an offline defrag followed by an online defrag is the recommended approach to drive optimization. After these two processes run, you simply need to schedule an online defrag. You can also set up a manual schedule. You can choose the drives to include in the schedule, the defragmentation type, and the date/ time you want the defrag to run.

Above and beyond. I appreciated Perfect- Disk’s ability to schedule an offline defrag (it will automatically reboot the server for you). The product can also “pause” the offline defrag after it has finished so that you can see the results. Active Directory (AD) integration lets you not only deploy the software but also configure it through Group Policy.

Results
All three of these disk-defrag products installed flawlessly and worked as advertised. Each defragmented the very full test hard disk completely, except for a large 3.5GB file with 19 fragments. All the products struggled with that file, partially because there was little free space to work with. PerfectDisk struggled a bit more than the others on disks with little free space. The products did equally well on the disk with lots of free space, each removing all defragmentation in about 20 minutes.

I was impressed by Diskeeper’s innovative approach to keeping the hard disk constantly defragged. Diskeeper claims that although you can manually defrag and even run the tool under a set schedule, it isn’t necessary because the application constantly defrags in the background. Diskeeper cruised through the manual defrag but left half the fragments of the large file. The product’s high sticker price, along with the equally high price of the add-on Administrator tool, keeps Diskeeper from attaining the Editor’s Choice distinction.

O&O Defrag’s poor online and over-thephone support infrastructure damages the tool’s overall effectiveness. The company needs to implement a phone number that’s easier to call from North America, and it needs to enhance its support Web site. O&O Defrag also had trouble defragmenting the large file, actually raising the number of fragments.

Unlike Diskeeper’s continuous defragging, PerfectDisk uses a manual/scheduled defrag routine that’s similar to that of O&O Defrag, so you’ll have to schedule defrags. Although it’s the slowest of the three products, PerfectDisk does the best job of defragging the hard disk. The extremely low price—combined with its full feature set and free, forthcoming Command Center—sets it apart from the competition and earns PerfectDisk our Editor’s Choice award.