- Data Rescue II
- Drive Genius
- TechTool Pro
- DiskWarrior
- AppleJack
Drive Genius
Also by Prosoft, Drive Genius is a comprehensive hard drive utility. It can be used to verify and repair disk directory structures; it can also be used to rebuild directory structures from badly corrupted disks. Like most third-party tools, Drive Genius provides a better chance of recovering corrupted disks than Disk Utility.
Beyond identifying and repairing corrupted directory structures, Drive Genius offers an array of more-advanced features not found in Disk Utility. The first of them is defragmenting and optimizing the layout of data on a disk. Although the Mac OS X Extended (HFS+) and related disk formats are not as susceptible to fragmentation problems as other formats, such as the PC FAT format, fragmentation can still occur, particularly on disks that are (or at one point were) about 90 percent full. Defragmenting a disk so that all the data of each file is stored in contiguous sectors can improve performance. Optimizing a disk so all related data is stored together (in particular, applications and Mac OS X boot and system files) can improve performance even more.
Drive Genius also offers a secure erase feature that can be used to securely erase all data on a drive or just the free space of a drive, which results in a secure erasure of any previously deleted files. This is offered in Disk Utility and using the Finder’s Secure Empty Trash feature as well. However, the ability to securely erase a disk’s free space is helpful because it ensures that any files not deleted using the Secure Empty Trash feature cannot be recovered without the need to erase the entire disk.
Hardware-level features include the ability to test the physical integrity of a drive, scan for bad sectors, and conduct performance bench marks. Drive Genius also offers two other advanced features.
The first is direct editing of a disk’s sectors (something only very advanced users should think about doing). The second is the ability to resize existing partitions on a hard drive without reformatting the drive (along with the ability to create/format new partitions and delete existing partitions, which exists in Disk Utility). This is a feature that was not available to Mac users until a few years ago. It is a very useful ability that is also provided by MicroMat’s DiskStudio (which is not included in this list because that is its only feature). This feature has also been added to the command-line version of Disk Utility in Mac OS X 10.4.6, but it is available only for hard drives using the GPT partition table scheme—which cannot be used on startup disks for Power PC Macs.
Overall, Drive Genius is a great tool because it includes powerful disk-repair features and also because it incorporates a number of additional powerful and useful features. It is a good choice for support professionals as well as consumers looking for a multifaceted hard drive tool.