Give others easy access to shared files. Boot into different operating systems. Back up files without breaking a sweat. Run disk utilities on the road—no CD required. Speed up Photoshop and games galore. Are these merely geek dreams? No, this can all come true for you—without your spending a dime—if you partition your hard disk.
It’s easy to split your Mac’s hard disk into several partitions with Apple’s free Disk Utility. If you instead use the iPartition utility, you may not have to wipe your hard drive in the process. Partitioning can make your work easier, faster, and safer.
The Many Joys of Partitioning
Here are a few excellent reasons to partition your hard disk:
Quick Backups of Critical Files
You can make quick backups of in-progress work on your extra partition. Simply drag files or folders to it throughout the day. This is an easy way to protect important data as you work. (The same caveats about potential problems with the physical disk apply here.)
Stress-Free Shared Files
Tired of running into permissions problems when you share files with other users on your Mac? Use a partition to give others easy access to shared files. When you create a partition for this purpose, select it in the Finder, press Command-I, click on the Ownership & Permissions triangle, and then select Ignore Ownership On This Volume. This allows all users to access the files it contains, regardless of the permissions set for the individual files.
Some programs, including Adobe Photoshop, Apple Final Cut Pro, and other audio and video programs, run faster if you store their files on a dedicated partition. Why? Because Photoshop writes
—temporary files—to your hard disk, and these files can be big. Video files likewise take up a lot of disk space. In both cases, using a dedicated partition keeps these files together, allowing the programs to load, read, and write the files quicker. And gamers may want to install games on a separate partition. Some games, especially those with lots of video and graphics, run faster this way, because their files aren’t strewn across a crowded primary partition.
You may have heard that creating a partition for OS X’s swap files will speed up your work, but it won’t really make much of a difference. You’d see a speedup if you stored the swap files on a different
disk, but if you simply store them on another partition on the same disk, your hard disk’s heads will jump from one section of the disk to another to read them. You may even find that your Mac runs slower.
Linux and More
For the truly geeky, a partition is a great place to house other operating systems. Install Linux on a partition so you can try out your favorite
on your Mac. If you have an older Mac and still use OS 9 for running some programs or for specific hardware that isn’t OS X-friendly, put OS 9 on a partition so you can boot from it more easily. If you develop software, put different versions of OS X on different partitions and boot from them to test your work in progress. Choose the partition you want to use by holding down the option key at startup.
Roll Up Your Sleeves and Slice That Disk
Partitioning a hard disk in OS X is not rocket science, but you do need to take precautions. First and foremost,
back up your files.
Partitioning a hard disk with Apple’s Disk Utility deletes everything on the disk, so make sure you have a complete copy. Ideally, the best time to partition is when you get a new Mac or a new hard disk, since you won’t have to back up anything.
How Many, How Big?
Click on the disk icon on the left side of the window, and then click on the Partition tab. Unless you’ve already partitioned the disk, you’ll see one partition. Select the number of partitions you’d like to create from the Volume Scheme pop-up menu. They’ll all be the same size unless you click on one to select it, enter a name, choose a format, and select the partition size (See screenshot). Consider allocating about 20GB for the startup partition; as for the others, consider how you’ll be using them to choose a size.
If you’ve partitioned a disk other than the startup one, you’ll see the volumes appear on your desktop or in the Finder window toolbar immediately. If you partitioned your startup disk, the partitions will appear the next time you restart your Mac.
If you have an enormous hard disk filled with data, think twice before using Apple’s Disk Utility to partition it and erase all its contents in the process. A program such as Coriolis Systems’
($45) can create and resize partitions
erasing your hard disk. This can be a big time-saver, since you won’t need to recopy all your data. And it’s great if you’d like to resize partitions later.
iPartition gives you visual information about your disks and partitions, lets you resize partitions by dragging the pieces in a pie-chart display, allows you to add and delete partitions, and offers an abundance of formatting options. In fact, iPartition is one of the few OS X programs that allows you to format disks using dozens of file systems, including FAT, Linux, NTFS, Next, OS/2, and others.
Still back up all your files first. All it takes is a power outage while the program is working, and you’ll lose everything. Also keep an eye out for
($50), which should be available by the time you read this.
Kirk McElhearn is the author of many books, including
The Mac OS X Command Line: Unix under the Hood
Apple’s free Disk Utility can slice up your hard disk with just a few clicks.