Hands-On Review--Micromat's DiskStudio 1.0.1

Micromat is finally shipping DiskStudio, an application that creates and removes partitions on a drive without erasing the data on it. We saw DiskStudio demonstrated at Macworld in January and gave it high praise for its simplicity and utility. It seemed to work great at Macworld and it was scheduled for release in February. We are not sure why it took so long to come out but we are glad Micromat took whatever time was needed to ensure a bug-free disk utility. We ordered a copy from J&R Computer last week for $50. The Macworld pre-order show special had been $35--we are sorry now that we did not take Micromat up on the deal.

DiskStudio creates partitions on drives without disturbing the existing data by using the blank portion of the drive for the new volume or volumes. It also deletes partitions that it made or were made by Apple's Disk Utility, a utility application bundled with Mac OS X. DiskStudio also performs the standard disk functions of erasing a volume and erasing an entire disk.

One limitation is that it deletes partitions in the reverse of the order they were created from the intial volume, accumulating the free space into the next lower numbered volume. For example, if a drive is partitioned into three volumes and you want to delete the partition that created volume three, the freed space accrues only to the partition for volume two. Volume one remains the same size unless the partition to volume two is also removed. The data on a deleted volume is lost but not the data on the volume that receives the freed up space.

Another limitation is that DiskStudio will not delete the partition with a boot volume. So if you have a drive with two boot volumes on it, DiskStudio will not delete the partition and create one volume directly. One has to first erase the unwanted boot volume and then delete the partition. Actually, this is a minor inconvenience that protects one from accidentally deleting a boot volume's partition.

How well does DiskStudio work? In our experience, quite well. First, we deleted a 2GB test partition, the third volume on our G4 Cube's original 20GB internal hard drive. The first two volumes hold installations of Mac OS X Server 10.4.2 and Mac OS X Client 10.4.2.

We booted from the DiskStudio CD, a process that Micromat warns could take up to 10 minutes. In our case, the 450MHz G4 Cube booted off the DiskStudio CD in around two minutes. DiskStudio showed that the first two volumes were not partitionable because they are boot volumes but the third was. We selected the third volume, our test volume with a variety of old files and applications, and clicked the "Delete" button. Within a few seconds the third volume was gone and its 2GB of space had accrued to the second volume containing Mac OS X Client 10.4.2 where we needed more space. Both remaining volumes booted and ran our Cube with no apparent problems.

Then we deleted a separate Mac OS 9 partition from an original 12" 867MHz Powerbook G4. First, we erased the Mac OS 9 volume (number two) and then deleted the partition that created it. Our Mac OS X partition became a volume of 37GB after receiving the 15GB of space freed up by deleting the Mac OS 9 volume. We then created two additional volumes from the free space and deleted them to test DiskStudio's other functions. Afterwards, the PowerBook G4 booted and ran fine off the now single and larger Mac OS X 10.4.2 volume.

Micromat's DiskStudio is a handy disk utility. It is well worth $50 to be able to partition a drive without erasing the existing data and to delete an unused partition to create a volume with more space without disturbing the data on the now larger volume. Being able to do so saves an enormous amount of time reinstalling Mac OS X, applications and files. DiskStudio works great for us but heed Micromat's warning to first backup critical data on a drive before using DiskStudio on it, sage advice for using any disk utility. You never know what might happen. [Bill Fox]