Run only the programs you need
The more programs you run at once on your Mac, the more RAM you use and the harder your Mac’s processor(s) must work. If you notice things slowing down, it’s a good idea to look at the Dock and quit any open programs you aren’t actively using. However, there are probably other programs running, too.
Nix Login Items Your Mac likely has a good number of running programs that you didn’t launch yourself, and even some that you can’t see in the Dock. (The latter are commonly called background processes.) One way to cut down on this superfluous activity is to weed out items that launch automatically when you log in to your account. Go to the Accounts preferences pane, select your user account, and then click on the Login Items tab. Glance through the list to see if there’s anything you don’t want running. Quite a few programs automatically add themselves or their support processes, so you may find items related to software you tried and discarded, or to add-ons you thought you’d uninstalled.
If you find something you don’t want, simply select it and click on the minus-sign (-) button or press the delete key on your keyboard. If you don’t recognize an item, hold the mouse cursor over its name for a few seconds. A small tooltip will appear, displaying the path to the item—and hopefully providing some context for the item’s purpose. (Deleting an item from Login Items doesn’t quit it; doing so just prevents it from launching the next time you log in. If the program doesn’t appear in the Dock, the easiest way to quit it is to log out of your user account and then back in; alternatively, you can use Activity Monitor, in /Applications/Utilities, to quit background processes.)
Dump Dashboard Widgets Many of us regularly try out new and interesting Dashboard widgets. But like programs, widgets use memory and processor cycles when running. Keep open only those you regularly use. To quit a widget and free up any system resource it’s using, activate Dashboard (F12 by default), hold down the option key, and then click on the X that appears in the widget’s upper left corner.
How Often Weed out your Login Items list once every couple months (do it more often if you frequently try new software). Disable unused Dashboard widgets whenever you install a new widget.
Keep a clean machine
It’s important to keep your Mac clean—virtually and physically—for optimum performance. That means more than just clearing out unused files.
Tidy Your Desktop OS X treats each item on your Desktop as a separate window. That means every file and folder you store there uses memory and CPU resources. The more powerful your computer is, the more items your Desktop can hold without noticeable effects. But eventually you’ll see more spinning beach balls and slower Finder actions, so it’s a good idea to occasionally straighten up.
You may find it easier to sort through lots of Desktop detritus if you open the Desktop folder (your user folder/Desktop) itself. You can then browse your Desktop’s contents in list view and sort by type, date, or another attribute. File away or delete anything you can. If you must store lots of stuff on your Desktop, create a few folders there—for example, one for each project or each type of file—and put items inside those folders.
Keep Your Mac Free of Muck Many people underestimate the importance of keeping the physical structures of their Macs clean. Of course you want to keep coffee, soda, and other liquids from spilling into your keyboard or on your MacBook, but other, less obvious, substances can gunk things up.
For example, crumbs from months of working lunches can eventually interfere with your keyboard’s key switches, preventing certain keys from registering (not to mention that a dirty keyboard is, well, gross). Dust and pet hair can build up around your computer’s vents, and on internal components, preventing the cooling system from working properly. This can shorten the life of your computer’s components over the long term, and can also cause seemingly random lockups and shutdowns when your Mac overheats (see “Gumming Up the Works”).
Luckily, keeping your Mac clean doesn’t take much effort. You can use a damp (not wet) cloth to wipe down your Mac’s exterior, and compressed-air canisters work well for clearing the dust from your Mac’s vents and loosening much of the junk that’s fallen into your keyboard. (Don’t use a standard vacuum to try to suck away dust, as static electricity may damage your computer. If you want to use a vacuum, you need a special anti-static model.) For more information about keeping laptops and LCD displays clean, see “Notebook cleanup and protection”.
If you’ve got a Mac Pro or an older Mac tower, open it every few months and make sure there’s not a significant amount of dust inside. And avoid eating over your keyboard or typing with sticky hands.
How Often Tidy up your desktop whenever you start to notice Finder slowdowns, or when you can no longer quickly find a file you’ve put there. Clean your Mac once a month or whenever necessary. Inspect the inside of tower Macs every few months.
Calibrate your laptop battery
Today’s laptop batteries are much better than those of just a decade ago, but they’re not perfect. While current power cells no longer experience the memory effect—a phenomenon whereby repeatedly using only a portion of a battery’s full charge would lead to the battery being unable to provide its full charge—your laptop can still exhibit similar symptoms, such as shorter-than-expected use time.
This is because each of Apple’s laptop batteries includes a tiny processor that monitors the battery’s charge and usage and then provides OS X with an estimate of the remaining battery life; over time, these estimates can become inaccurate. The result can be your Mac alerting you that you’re about to run out of power, or your laptop abruptly going to sleep, when you should have more than enough juice left.
To avoid such problems, Apple recommends that you calibrate your laptop battery once a month to get the battery and its microprocessor back in sync. Basically, this involves running your battery down until it’s completely depleted, and then charging it back up to its full capacity. However, the exact procedure depends on your Mac laptop model; see Apple’s instructions for calibrating different Mac model batteries.
How Often Recalibrate your laptop battery once every month. Apple hosts an iCal calendar, with monthly reminders, that you can subscribe to, or you can use the reminders in the downloadable Macworld Maintenance Calendar.
[Senior Editor Dan Frakes has been writing about Mac maintenance and troubleshooting since the early days of the Power Macintosh.]