Alsoft DiskWarrior is
a disk repair utility that resolves directory damage to files and folders by building
a replacement directory from data recovered from the original directory. The replacement
directory is optimized, thus speeding up overall disk performance. Disk Warrior will
work on any Mac OS Standard (HFS) or Mac OS Extended (HFS Plus) disk even if the
Finder cannot mount it and display it on the desktop.
DiskWarrior fixes wrapper volumes, master directory blocks and alternate master directory
blocks (HFS), volume headers and alternate volume headers (HFS Plus), volume bit
maps, catalog trees, and extent trees.
DiskWarior cannot rebuild the current startup disk or any disk from which it is running.
DiskWarrior can repair any Mac SCSI, USB, FireWire, IDE, or RAID disk meeting the
above requirements. DiskWarrior rebuilds directories on disks as large as 2,000 gigabytes
- Mac OS X 10.2 or
- 128 MB Physical RAM
(256 MB recommended)
- 6MB disk space
Pismo G3 powerbook,
Mac OS X 10.2.8 (Jaguar), 768MB RAM, 400MHz
2.1 is included on the DiskWarrior 3.0 CD for Mac OS 9 and earlier systems. This
review only addresses DiskWarrior 3 for Mac OS X.
The software comes on a bootable OS X 10.2 Jaguar CD, so it will boot all the latest
computers except the new G5's and PowerBooks manufactured since September 2003. The
CD also contains DiskWarrior 2.1.1, which was the last Classic version.
To run the application, just insert the CD into your CD-ROM drive and restart your
Mac while holding down the 'C' key to boot off the CD. DiskWarrior opens with the
main window displaying the mounted drives in a pop-down list box. Select the drive
you want DiskWarrior to rebuild and click the 'Graph' button.
While DiskWarrior is known mainly for fixing disk problems, it can (and should) be
used for preventative maintenance. Run DiskWarrior on one of your volumes, and it
creates a graph that indicates the degree your directory is internally fragmented
(the term directory is used to represent the entire file catalog on a volume). Each
part (node) of the directory is assigned a color along a gradient between white and
dark blue depending upon its optimized position. The graph of a perfectly optimized
directory is a perfect gradient from white to blue. Fragmentation interrupts the
gradient. The more distant a fragment is from its optimized position the greater
the difference between the color of the fragment and the color of the same position
in an optimized graph.
I try to run DiskWarrior once a month. When I first ran it, 7% of my directories
were corrupted. I clicked the "Rebuild" button, and then took a break while
DiskWarrior crawled through my hard drive's directories building a preview report
of all the errors and what it wants to do to correct them. This process takes time,
and it's an interactive process. It doesn't actually perform the "rebuild"
until step number 10. The amazing thing about the disk preview report is that it's
kept in memory until the actual rebuild takes place. This provides two benefits.
First, because no disk I/O is performed, if you have a power failure or your computer
crashes, your disk is unchanged.
The other benefit of keeping the report in memory is that it gives you the opportunity
to preview and cancel the operation without changing the disk. You can preview the
disk report, and if not all of your files are recoverable (e.g., physical damage
to disk or partially overwritten files), you can copy specific files from the preview
disk to another disk, and then cancel the rebuild. By choosing to cancel, your disk
is left unchanged. Other disk utilities, such as Norton Disk Doctor, perform disk
I/O during repair operations, so once the process begins, you are vulnerable to power
outages, and you are not offered the opportunity to cancel and leave your disk unchanged.
At first I thought the only time your disk would be vulnerable to a power outage
is during the actual step where the new directory is being written to your disk.
However, DiskWarrior resolves that concern by using a fail-safe method of installing
the new directory. When DiskWarrior writes the new directory to your disk, it first
writes the rebuilt directory to free space (which requires that you have at least
enough free disk space to hold this temporary directory). Once this new temporary
directory is in place, DiskWarrior instructs the system to use the new directory,
and performs tests on it. After the tests, the new rebuilt directory is then copied
over the original directory and the system is instructed to use it (the temporary
directory is set back to free space). If the OS is interrupted while writing to the
temporary directory, your system boots up under the old directory and you can then
run the rebuild again. If the OS is interrupted while copying the temporary directory
over the permanent directory, the system boots up using the new directory. Your directory
is never at risk.
DiskWarrior also comes with a monitoring feature. You have the option to install
DiskWarrior on your hard drive, enabling DiskWarrior's hardware monitoring capability.
This feature uses a drive's built-in SMART technology (Self-Monitoring, Analysis,
and Reporting Technology). Currently OS X does not report errors from SMART hard
drives, but DiskWarrior provides the ability to monitor a SMART hard drive and report
a pending drive failure. This is a critical feature because it could provide an indication
of a failing drive, giving you the opportunity to backup data before the drive fails
completely. This feature does not currently work on SMART SCSI drives.
If you own another disk repair utility (e.g., Symantec Norton SystemsWorks), run
DiskWarrior first! Other utilities patch the directory, so you run the risk of loosing
directory data, making it impossible for DiskWarrior to completely recovery the directory
The DiskWarrior 3 CD contains a Quick Start Manual and a PDF version of the full
DiskWarrior Manual. More info can be found at the DiskWarrior home page.
DiskWarrior 3 is a remarkable disk repair utility that is very easy to use. I like
the graphical interface, which depicts the directory corruption. I have owned the
previous OS 9 Classic version of DiskWarrior 2.1.1, and the OS X version stays true
to form (in terms of functionality and ease of use).
I miss the disk optimization program called PlusOptimizer, which is part of the classic
version of DiskWarrior. Defragmentation is a desireable feature and would make the
DiskWarrior package more complete. It would also be nice if Alsoft provided academic
pricing like Symantec does for Norton SystemWorks.
The bottom line, however, it that this utility does wonders for disk repairs and
preventative disk maintenance. It completely rebuilds your hard drive's directory,
keeps the new directory in memory for preview and cancel options, and provides a
fail-safe method for writing the new directory to your disk. DiskWarrior 3 is an
indispensable disk repair tool that belongs in every Mac user's toolbox.
- Rebuilt directory
kept in memory with preview and cancel options
- Fail-safe method
of updating the directory to disk
- Runs native in OS
- SMART internal diagnostic
routine detects hardware malfunction
- No SCSI support for
- Can be slow to recover
a large volume
- Does not yet boot
in 10.3 (i.e., won't boot on new G5's)
- Does not include
out of 5 Mice