There are still benefits, but it’s definitely not for everyone.
If you’ve been around computers for a while, you may remember a time when you would hear people talk about needing to defragment their hard drive, particularly if they used a PC, where there is a built-in utility. With Macs, however, the story is a little different.
Since Mac OS X 10.2, a lot of file defragmentation is handled by the file system, such that files under 20 MB are defragmented automatically. So if you find that your Mac is running slowly, odds are that it’s not actually a result of fragmentation. The exception to this relates to files larger than 20 MB. If you deal with large graphics files, video, or other large-format data, then you may benefit from defragmenting if you use a standard rotational hard drive, and you experience delays when dealing with those larger files.
How to defragment on a Mac
As mentioned above, however, Macs don’t include a built-in defragmentation utility. For this, you’ll need to turn to third party utilities. Three options to consider are iDefrag, Techtool Pro, and Drive Genius. iDefrag does only defragmentation and has more defragmentation options, but is no longer supported after macOS 10.12. Techtool Pro calls defragmentation “optimization,” and offers tools to optimize both whole disks and just files over 20 MB. Drive Genius also includes a Defragment function. With any defragmentation, be sure to make sure your data is backed up first. If unexpected errors, power surges or outages occur during a defragmentation, you may lose data.
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