The good Stephen Good is concerned about his Mac’s performance. He writes:
Do too many apps slow down a Mac? System Profiler lists 375 on my G5 iMac. I could remove tons of them with AppZapper, but would that quicken my system?
I can answer that question with a definite maybe . I waffle and weave because the absence of an application may help performance depending on what the application is doing in both its work and off-hours.
For example, if the application runs some background job that’s placing demands on your Mac’s processor, the existence of the application could slow down performance. I use Ambrosia Software’s terrific screen capture tool, SnapzPro X 2. A gander at Activity Monitor tells me that even though I’m not doing anything with it, it’s taking up about 0.50 percent of my CPU’s attention. I’m not suggesting that Snapz is doing any harm with such pitiful demands, I point to it only to illustrate what background processes can do.
With that in mind, put Activity Monitor to good use and see which background processes appear at the top of the list when you sort by % CPU. If they’re apps you can do without, getting rid of them may help performance.
If an application requires a login item—you have a backup program that requires a scheduling component that monitors your Mac behind the scenes, for example—it can take your Mac longer to boot up. Again, if you don’t need the application, getting rid of it (and its accompanying login item) may bring you to the Desktop a little bit more quickly when you first start your Mac.
And open applications can suck on the CPU as well. For instance, I have Microsoft Word open while I type this entry in BBEdit. Word’s doing absolutely nothing, as far as I can tell, yet Activity Monitor tells me that it’s using between 3 and 4 percent of the CPU. And I’ve found that if I leave a browser open for days on end, performance can wane as well. Quitting and relaunching the browser helps.
So, try quitting applications when you’re really and truly done with them. If you find that one of your apps is sucking more of your computer’s oomph than you care for, see if you can find a less processor-hungry alternative.
Looked at your Dashboard widgets lately? Third-party widgets can distract your processor too. See what they’re doing in Activity Monitor. Clear out the more processor hungry widgets that you installed out of curiosity but never use.
Finally, if your Mac is so crammed with applications (and other kinds of data) that you have very little room left on your hard drive, performance is going to suffer because the OS uses free hard drive space for its virtual memory scheme. At the very least I try to leave 10 percent free space on my startup drive so the OS has room for those virtual memory chores.