Fix Mac slowdowns

Does your Mac seem to be getting slower over time? This probably isn’t your imagination. As you use your computer, a number of factors can gradually lead to poorer performance. Things slow down as your CPU becomes busier with more tasks, your RAM fills up with open programs and documents, and your hard drive runs out of free space. In addition, individual programs, such as your Web browser and your e-mail client, occasionally need some tweaks to maintain peak performance. Luckily, it’s easy to solve most slowdowns and restore much of your Mac’s original pep.


Web browsing is too slow

When Web pages take a long time to load, or when your browser becomes generally sluggish, you may suspect that your Internet connection is too slow. That’s possible, but if you have a reliable broadband connection, the problem is more likely something you can easily solve. Try these tips.

Quit and Relaunch Web browsers tend to be resource hogs, and if you visit lots of media-rich sites, this effect can increase over time. Quit and relaunch your browser occasionally (at least once a day) to speed up browsing and reduce your browser’s impact on other programs.

Close Tabs and Windows Do you keep lots of tabs or windows open? Each one uses RAM, and some of them can also bog down your processor, even when you’re not actively viewing that page. If your browser’s performance is poor, try limiting yourself to six or eight open Web sites at a time.

Try a Different Browser There’s no easy answer to the question “Which browser is fastest?” It depends on your Mac’s processor, which version of OS X you’re running, and which version of a given browser you’re using. What you’re doing—for example, playing a Flash game or looking at a CSS-rich site—matters, too. My advice is to consider trying a different browser if yours feels too slow. You may get the best results from Apple’s Safari 3, Mozilla’s Firefox 2, The Omni Group’s OmniWeb, or Opera Software’s Opera, depending on the circumstances.

E-mail takes forever

Speed Up Entourage: Use Entourage’s hidden Database Utility to repair your index of e-mail messages and, in the process, fix performance problems.
Does checking your e-mail or searching for a saved message seem to take an eternity? Several strategies can help solve this problem.

Clean Out Your Inbox If you have thousands of messages in your inbox, your e-mail client can get bogged down. Apple’s Mail (/Applications) is especially sensitive to inbox size when you’re using IMAP, a common mail protocol that keeps copies of your messages on the server. Filing messages you’ve already read reduces the amount of work your e-mail client must do every time you check your mail.

Rebuild Your Message Index Both Mail and Microsoft Entourage (part of the $399 Microsoft Office 2004,  ) store indexes of saved messages in special databases. This facilitates displaying, sorting, and searching your messages. Over time, though, these databases can become cluttered or even corrupted, resulting in slower overall performance, among other problems. You may be able to speed up your e-mail client significantly by rebuilding the message index every few months.

Mail’s Rebuild command (Mailbox: Rebuild) works only on individual mailboxes. To rebuild all your mailboxes in all accounts at once, try one of two utilities: Matteo Discardi’s Speedmail (donation requested) and Leland Scott’s VacuumMail (free). The latter can run on a schedule.

To rebuild your database in Entourage, hold down the option key while launching the program. In the Database Utility window that appears, select an identity (if you have more than one). Select Rebuild Database and click on Continue (see “Speed Up Entourage”). Click on Done and then on Quit when the process is finished (it can take a while). After you relaunch Entourage, it will have to redownload any previously retrieved messages from your IMAP account(s).

Check on Progress Your e-mail client may be simultaneously sending and receiving messages from multiple accounts, synchronizing mailboxes, and performing other background tasks—or it may just be stuck. If you can find out exactly what it’s up to at any given time, you’ll be able to solve potential problems.

In Mail, choose Window: Activity Viewer. The small floating window that appears lists each task Mail is performing. If one task appears to be taking an inordinately long time, click on the Stop icon next to it to cancel that task. In Entourage, choose Window: Progress. Again, a window lists each current task; click on Stop to stop a single task, or on Stop All to stop all interaction with your mail servers. If you experience persistent misbehavior in Entourage, choose Window: Error Log to display a list of error messages, which may give you clues that help you diagnose the problem.

Consolidate Accounts Do you have more than a couple of e-mail accounts? Though most e-mail clients can check as many accounts as you have, each additional account means a longer wait when you check for new messages. One way to speed things up without getting rid of any e-mail addresses is to redirect all your incoming messages to a single account. For example, if you use Apple’s .Mac mail ($100 per year) and Google’s Gmail (free) for secondary e-mail accounts, you can set up both to forward incoming mail to your ISP, and thus get all your mail at one account—cutting the amount of checking that has to happen by two-thirds. (You may find this particularly valuable if you have a slow or unreliable Internet connection.)

Each e-mail provider has a different mechanism for setting up forwarding. If you’re a .Mac subscriber, log in to your account, click on the Mail link, and then click on the Preferences link. In the Other tab, select Forward My Email To and fill in the address that messages should be sent to; then click on Save. If you have a Gmail account, log in, click on the Settings link, and then click on the Forwarding And POP/IMAP link. Select Forward A Copy Of Incoming Mail To, enter the address, and click on Save Changes.

Everything is too slow

If everything you do on your Mac seems to take much longer than it once did, look for several common system problems, as well as individual programs that are outdated or are simply using more than their fair share of your Mac’s resources.

Run Fewer Programs Take a look at your Dock, and notice how many programs are currently running. (In OS X 10.4, you can tell what’s running by looking for a black arrow below program icons; OS X 10.5 uses a glowing blue orb.) Each one of these programs, even if it has no open windows, is consuming a certain amount of your Mac’s RAM and processor power. You can reduce the strain on your system by quitting the ones you’re not actively using.

Restart Your Mac If you normally leave your Mac running all the time, performance can deteriorate. One reason for this is a relatively common kind of bug known as a memory leak: a program keeps asking the system for ever greater amounts of RAM. Another reason is that the longer you use your Mac in a given session, the likelier you are to launch additional programs (including invisible background processes) that use up system resources. The easiest way to clear all your memory and zap hidden programs is to restart.

Add More RAM The more RAM your machine has, the more programs and documents you can have open at the same time without relying heavily on virtual memory. (To use RAM as efficiently as possible and let many programs run at once, OS X’s virtual- memory system temporarily stores data on your hard disk instead of in RAM.) As a result, adding RAM—up to a certain point—is one of the most effective ways to speed up your Mac. The amount you install will depend on the capacity of your machine and your budget, but I recommend 2GB to 4GB for most people.

Update Your Software The software on your computer—including OS X itself—may have bugs that diminish overall performance. So I recommend keeping up with software updates. Choose Apple Menu: Software Update to check for the latest versions of OS X and other Apple software. For third-party applications, look for a Check For Updates menu command or consult the developer’s Web site. Microsoft Office, for example, comes with a utility, Microsoft AutoUpdate (/Applications), that checks for and downloads Office updates. Another useful tool is Georg C. Kaindl’s free Dashboard widget App Update. It checks all your programs against the latest available versions recorded at sites such as and MacUpdate .com. It then lists the ones for which newer versions are available.

Repair Your Disk The sorts of random minor errors that can crop up on any hard disk over time may slow down your computer. To check for such errors and repair them, start your Mac from your OS X Install disc. (To do so, hold down the C key while starting up with the disc installed.) Then choose Utilities: Disk Utility, select the startup disk from the list on the left, and click on Repair Disk in the First Aid tab. Alternatively, use a third-party utility such as Alsoft’s $100 DiskWarrior 4 ( ) or Micromat’s $98 TechTool Pro 4 ( ). Start up from the program’s emergency disc to run the repair software. Or if you have a bootable duplicate of your disk on an external hard drive, you can start up from that and run Apple’s Disk Utility or another tool.

Defragment Your Disk As you use your computer, individual files get split into numerous pieces on your hard disk, a state known as file fragmentation. In addition, the files or file fragments may be scattered all over your disk, reducing the amount of contiguous free space; this is known as disk fragmentation. Ordinarily, neither condition is problematic, given today’s large, fast hard drives—so for most people, defragmenting a drive has little (if any) benefit. However, fragmentation can become a real problem when your disk is nearly full or when you’re running lots of programs that depend heavily on virtual memory. Your drive must do extra work to reconstruct all the pieces of every file it uses. Fragmentation can also be a problem with audio or video programs that must transfer very large chunks of data to or from your disk in real time, and that therefore function much better when there’s enough free space to store those files in contiguous units.

OS X automatically defragments smaller files, but larger ones may still be in many pieces. And merely rejoining individual files into contiguous segments doesn’t address the problem of disk fragmentation. Therefore, if you think your Mac is spending far too long reading and writing files on disk, you may benefit from defragmenting (or “optimizing”) your hard disk on occasion—say, once or twice a year.

Several utilities can do this for you, including TechTool Pro, Coriolis Systems’ $35 iDefrag 1.6.4, and Prosoft’s $99 Drive Genius 1.5.3 ( ). Note that you should always have a recent, full backup of your drive before defragmenting. The process can take many hours, depending on the size of your drive and its level of fragmentation.

Another way to obtain a (mostly) defragmented disk is to duplicate it onto another disk, using a program such as Shirt Pocket’s $27 SuperDuper 2.1.2 ( ) or Mike Bombich’s Carbon Copy Cloner 3.0.1 ( ). Use Disk Utility to erase the original disk, and then reverse the duplication procedure, copying all the files from your backup to your main disk. This process is generally faster and less expensive than running a defragmentation utility, but it does require that you have an extra hard disk or partition available.

A Full Disk Is a Slow Disk: The Get Info window tells you how much empty space your hard disk has. To get the best performance from OS X, you should have at least 10GB of free space.
Check Disk Space If your hard disk is within a few gigabytes of being full, you risk running out of space for virtual memory, and you increase the probability of significant disk fragmentation. You can check your disk’s free space by launching Apple’s Activity Monitor (/Applications/Utilities) and clicking on the Disk Usage tab. Alternatively, select your hard-disk icon in the Finder, choose File: Get Info, and look at the Available amount under the General heading (see “A Full Disk Is a Slow Disk”).

If your disk is too full, delete seldom-used files or programs (after backing them up, of course). One way to look for such items is to choose File: Find in the Finder, select Computer, and then use the pop-up menus to set a Last Opened Before date that’s a year or more in the past. Your goal should be to have at least 10GB of free space. (If you’re perpetually close to your drive’s capacity, you should consider upgrading to a larger drive.)

Look for Hidden Programs Along with the programs that appear in your Dock, numerous components of OS X (as well as third-party programs) run without your launching them—either continuously or as needed. This is normal and good, but problems can arise if too many background processes are running, especially if they have memory leaks or other bugs.

Use Activity Monitor to find out what’s running. Don’t worry if it lists numerous items you don’t recognize, but pay attention to programs that have high %CPU and Real Memory figures (CPU and RSIZE, respectively, in OS X 10.5). If you don’t need them, it’s possible to use Activity Monitor to quit them (see “What’s My Mac Doing?”).

If you’re using an Intel-based Mac, you may have performance problems with programs that weren’t written for your computer’s processor. Check Activity Monitor’s Kind column to see whether a process is running natively (Intel) or using Rosetta emulation (PowerPC). (If the column isn’t visible, choose View: Columns: Kind to display it.) PowerPC applications running on an Intel processor require extra CPU power; check with the developers to see if a Universal update is available.

Check for Unwanted Widgets and Login Items Finally, remember that all the add-ons and system enhancements you’ve installed—Dashboard widgets, menu extras, preference panes, and the like—come at a cost. Each one uses a certain amount of RAM and CPU power and can make an impact on your Mac’s performance. And be sure to check the list of Login Items in the Accounts preference pane. If you see items in this list that you no longer use, select them and click on the minus-sign (-) button to remove them. Then either restart, or log out and log back in.

[Joe Kissell is the senior editor of TidBits and the author of the e-book Take Control of Troubleshooting Your Mac (TidBits Publishing, 2007).]


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