- 0 Comments
- 0 Recommendations
Five Mac maintenance myths
You know you need to change the oil in your car every 3,000 miles, clean your house’s gutters every fall, and brush your teeth at least twice a day—but do you know what’s necessary to keep your Mac in good shape? For the most part, Macs run smoothly. But as with most machines, a little preventative maintenance goes a long way toward keeping things running smoothly.
This week, in our Essential Mac Maintenance series, I’ll show you what you need to do, starting today with how to Get Set Up. But first, let’s talk about what you don’t need to do, despite what you may read in online forums or on email mailing lists. I call these things maintenance myths.
Myth #1: “You should repair permissions regularly.”
OS X’s permissions determine the access each user has to each item on a hard drive. If certain files have the wrong permissions, you can experience problems. So you’ll commonly hear that you need to use Disk Utility’s Repair Disk Permissions feature on your startup drive as a routine maintenance procedure.
But contrary to popular belief, repairing permissions—a procedure which simply resets permissions to a known state—works only on a particular subset of OS X system files. It doesn’t affect user files, nor does it affect third-party files or programs. In other words, it’s unlikely that regularly repairing permissions will prevent problems.
If you ever do have a problem with system-level permissions, your Mac will likely behave oddly, and you’ll usually be able to use the Repair Disk Permissions function then to fix the problem without any data loss or long-term effects. So I recommend repairing permissions as a troubleshooting tool rather than a maintenance task. For a comprehensive look at this topic, see Repairing Permissions: What you need to know.
Myth #2: “You need to run the Unix maintenance scripts.”
You may have heard about a collection of magical Unix maintenance scripts that OS X is supposed to run automatically. The story goes that because these scripts are scheduled to run in the middle of the night, putting your Mac to sleep or shutting it down prevents them from running—so you need to do so manually.
It’s true that there are Unix scripts that perform certain cleanup tasks in the early morning—one script every day, a second script once a week, and a third once a month. It’s also true that if you shut down your Mac every night, the scripts don’t run. However, the situation isn’t as dire as you might think. First, if you put your Mac to sleep at night, instead of shutting it down, Leopard is smart enough to run the missed scripts the next time you wake up your computer. (Tiger is supposed to do so, as well, although this automatic feature didn’t work as well.) Second, the tasks these scripts perform aren’t so important that a few missed executions will adversely affect your Mac.
The main script tasks involve cleaning out old log and temporary files and rebuilding Unix’s locate and whatis databases. If you’re a Unix geek, leave your Mac on (or asleep) on Friday nights so the weekly script can run at its normal Saturday-morning time. If you’re not a heavy users of locate or whatis, you’ll likely be fine running the scripts every few months just to clean up your log files. An easy way to run the scripts manually is by using Mike Vande Ven Jr.’s free Maintidget 1.3, a Dashboard widget that shows you the last time each script was run and lets you manually run one or all with a single click. There are also innumerable tweaking utilities that provide similar functionality
Myth #3: “You should periodically defragment your hard drive.”
If you save a file to your hard drive when there isn’t a large-enough block of contiguous free space for it, the file is broken into several smaller pieces. This is called file fragmentation. Some amount of file fragmentation is normal, especially as your hard drive gets full. But too much file fragmentation hinders performance—the more fragmented your drive is, the harder it has to work to read each file.
Because of this, people have long recommended defragmenting drives—regularly using a utility to rearrange file fragments on your hard drive so that each file resides in a contiguous block of hard-drive space—as routine maintenance. But with OS X, this procedure isn’t necessary for everyone, for several reasons. First, the Mac’s file system, HFS Plus, is quite good at avoiding file fragmentation. Second, the performance of today’s hard drives is so good that many users won’t notice even moderate fragmentation. Finally, OS X (10.3 and later) automatically defragments some files.
File fragmentation is an issue primarily for people with almost-full hard drives and people who work with very large files or large amounts of data (for example, video and some image files). If your drive is almost full, a better option is to free up space or upgrade to a larger drive. People who truly need to defragment—or optimize, which is defragmentation that also attempts to position particular types of files for optimal performance—can use utilities such as Prosoft Engineering’s $99