MacTip: Overfilled hard drive

One problem I am seeing more and more of lately is an overfilled hard drive. Huh?, you may ask. What do you mean by that?

What I mean is a hard drive that is so filled with stuff – documents, speadsheets, digital photos, music, movies, other downloads, as well as applications, the operating system and its files – that there may be only 1 percent to 5 percent free space left.

What's wrong with that? Isn't that where that stuff is supposed to be stored?

Yes it is, except you need to keep at least 10 percent of your Mac's hard drive free of permanently stored stuff (some experts say more, but I think 10 percent is enough). Why? Because Mac OS X needs that free space in order to "page out," or use virtual memory to temporarily store information.

Virtual memory is when the Mac temporarily shifts information from random access memory, or RAM, onto unused portions of the hard drive. It uses free space on the hard drive to do this. If nearly all of the hard drive is filled with permanently stored data, then Mac OS X can't use virtual memory, and starts to behave erratically, even failing to carry out tasks.

The solution? Make some free space on the hard drive. Start by emptying your trash, and re-emptying it periodically. Get another internal hard drive installed (if your Mac can have another drive) or buy and install an external hard drive, and copy stuff onto it from the internal hard drive, then delete the stuff you copy from the internal drive.

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