The Great Defrag Shootout X: Diskeeper 2007 Professional and Pro Premier

This has been the most difficult review to write, because I feel like I'm swimming against the tide of public opinion, and I've had bad experiences with Diskeeper in the past. It's also the most expensive product reviewed. As time went on the review became easier as using the product became more loathsome.
It's also the first product I have ever encountered that is both paranoid and self-defeating. When you install it, it removes the built-in Windows Disk Defragmenter (WDD), and even replaces the icon in the "Start->Programs->Accessories->System Tools" menu with its own. I assume this is to ensure that it is used for disk maintenance, rather than WDD. But the sceptic in me tells me Diskeeper doesn't want you to see that it isn't much of an improvement from WDD; hence "paranoid". It's self-defeating because the help file basically admits it can't work properly when free disk space gets low. Consider this extract:

Getting More Free Space

If your volume is extremely full, there may not be sufficient free space to effectively defragment the files. In this case, here are several suggestions:
You can temporarily move some of the files off the volume, particularly large files. This temporary measure often allows Diskeeper the "working room" it needs to complete the defragmentation process. Also, this allows Diskeeper to defragment the free space on the volume, increasing the possibility that the temporarily-moved files can be moved back to the volume in a contiguous (or at least less fragmented) condition.
There are often a number of temporary files stored on your computer, and deleting these files can help you gain more free space. [snip]
You can empty the Windows Recycle Bin on the volume in question. By default, when you delete files on most Windows systems the files are not really deleted—they are instead moved into the Recycle Bin, so they still take up disk space. Emptying the Recycle Bin does delete the files, thus creating more room for Diskeeper to do its work.

While I agree that a simple program like CCleaner will reduce the clutter on your PC, the reason why I needed a program other than WDD was to sort out the tangled mess my large files were getting themselves into that WDD wasn't able to sort out. I fail to see why I should keep 15-20% of my drive unused simply because my defrag program can't deal with my large files. That's what Diskeeper expects.

Why doesn't Diskeeper completely consolidate the free space on my volume?
There are several factors that can prevent the free space on a disk volume from being defragmented:

• A fragmented paging file.
• A large number of directories on the volume.
• On NTFS volumes, a portion of the free space on a volume is reserved by the operating system for the Master File Table (MFT).

It is important to know that having all of the free space in a single, contiguous piece provides very little (if any) performance benefit. Free space fragmented into hundreds of pieces will impact disk performance, but free space that’s in a few pieces should not have any effect on the performance of your disk.

So on the one hand Diskeeper doesn't make any major effort to sort out the free disk space, and on the other hand it states that if there isn't enough free disk space it can't (or won't) defrag large files. This is a self-defeating approach, and when it hits you you'll wish you never paid good money for this program. Just uninstall it and buy a decent program to begin with.
It's slow. Very slow. Not all the time, mind you, but in the case of my C: drive it took anything up to 20 minutes, and always longer than 10 minutes, just to analyse the drive; other programs reviewed took less time to defrag the drive. Removing certain crucial large compressed files fixed this, but I need those files! The image above shows the analyse screen after 11 minutes, timed using DS Clock. Not even WDD takes that long!
There seems to be a flaw in Diskeeper that prevents it from dealing correctly with large, compressed files, fragmented or not. Apart from slowing the analyse process down, once the analysis is complete it shows the wrong answer. This may explain the problems I encountered in actually getting the drive defragmented. In the picture above it is getting the size of the file wrong because it only occupies 1441MB, not 3488MB as shown, so its "Excess Allocation" error message is misleading. On another occasion it clearly showed some red fragmented files on the screen, but the list of fragmented files was completely empty.
I enabled the automatic background defragmentation process, and noticed the hard drive activity increased, especially when I wasn't busy. The user interface has a time line which shows how many fragments have been removed on a daily basis, and also the maximum and minimum number of fragments present on each drive. Presumably this is done to show how well Diskeeper is doing. Conversely it also shows how much Diskeeper isn't doing. The total of over 6000 fragments were generated through normal PC use in spite of their "revolutionary InvisiTasking™ technology" which is supposed to defragment the machine on the fly.
The program is fairly easy to use, and it has some nice interface and information features, but no way of being able to associate a given red area on the drive map to a particular file.
Diskeeper has a concept of "just enough" fragmentation of large files, where it will not use excess time and resources to further defragment a "large" file if there is no performance improvement. Even with this disabled, Diskeeper is not good at defragmenting large files. Here are 3 successive attempts at getting my hard drive tidy using the "Professional" version:
In each case Diskeeper has ignored some files, and not made any attempt at consolidating the free disk space. This is the same problem I experienced with Diskeeper version 7 and 8.
In desperation I uninstalled the $49.95 Professional version and tried the even more expensive Pro Premier ($99.95) version. It is the most expensive product in this category, and also the most underwhelming. I wanted to see if the "Intelligent File Access Acceleration Sequencing Technology" or I-FAAST™ feature would make a difference. It did (see below), but certainly not $50 worth!
The default setting in Diskeeper is to detect removable storage devices, so when I inserted my iPod Shuffle, DKSevice.exe crashed. After rebooting the PC and disabling removable drive detection, no further problems were encountered.
The "revolutionary InvisiTasking™ technology" doesn't work as well without the I-FAAST™ feature, and when it does work, it doesn't notice when you start using your machine again. I happened to double-click on an MP3 file it was busy with, and got a nasty error from WinAmp. A few minutes later the file played fine.
The picture above was taken on Sunday at 4pm, after I had removed the 2 large SQL data files, defragmented the drive without them, and then put them back. You can see how the compression process fragments the files.
Five hours later, with a bit of prodding by getting Contig to defrag all the other files on the drive, this is the result. I was unable to get this with Diskeeper 2007 Pro, only with Diskeeper 2007 Pro Premier, and only after specifically identifying the two files as being priority files for the I-FAAST system.
I guess that in terms of the Diskeeper hype-powered marketing pitch, that makes me a gullible "power user" who will happily part with $100 just to keep his disk tidy. I was suckered once, I'm not going to be suckered a second time. For $100 I could buy both Vopt 8 and PerfectDisk 8, with change to spare. Either one of them could do a better job, and faster too.
I also find the Diskeeper install process somewhat insulting. They create a "Diskeeper Corporation" program group in "Start->Programs", and then put a single icon in there. Why? No uninstall, no link to their web site, no help file, nothing. If there is only one icon, just do me a favour and put it in "Start->Programs" and save me some time, FFS!
I have left the best feature till last: the uninstall. Unlike version 8 which left residue that made WDD unworkable until I hacked it, this one does restore WDD when you uninstall Diskeeper. I recommend uninstalling it. I did. Twice. Even so, Diskeeper 2007 it left a desktop shortcut behind and a reference in the registry to AUTONTFS. Have these people no shame?

I have not decided what to review next: DiskMD didn't make it out of the starting block, since you have to buy it before you find out whther it's any good. In the meantime, I suggest you try my combination of freeware defrag utilities. Download it here. It's certainly better than Diskeeper.

Update: Monday 28th May 2007: It seems that Diskeeper is one of the only programs actually able to defrag the Master File Table (MFT). Because I converted my FAT32 partition to NTFS before I had reinstalled everything, the MFT doubled in size while I installed all the Office files and other applications. After trying PerfectDisk 8, JkDefrag, and Windows Disk Defragmenter, Diskeeper did the trick. When I uninstalled it I didn't get the errors reported above. I have contacted Raxco to find out why PD wasn't able to defrag the MFT, when it claims to be able to so. I did not receive a reply.
Update: Friday 8th June 2007: It would appear that Paragon Total Defrag 2007 can not only defragment the MFT, but also reduce its size, something no other defrag program can do.
Update: Wednesday 24th October 2008: DK 2008 has been released, and I'll be testing it for the next few weeks to see if it really lives up to its claims. I'm not optimistic but I hope to be proved wrong. See First Impressions.

The Great Defrag Shootout: Part I | II | III | IV | V | VI | VII | VIII | IX | X | XI | XII | XIII | XIV | XV | XVI | XVII | XVIII | XIX | XX | XXI | XXII | XXIII | XXIV | XXV | XXVI | XXVII | XXVIII | XXIX| winner | all | why | digg story | Benchmarks: DK2008 and DK2007