Jun 14, 2013

How much space should be kept free on hard drives?

I’ve heard people say that a wide range of space should be left free on a hard drive for best performance - anywhere from 5%, which seems too low, to 50%, which seems too high. So if I have a 2 TB drive, there should be 1 TB of free space? Riiiiiiiight. Is there actually a rule of thumb to follow on this?


50% free is more than necessary. Of course the drive will get slower as it gets close to full, but that is excessive. Even 15% or so should still be enough free for everything to load and work. That’s just a guess though, as jimlynch noted there are a lot of variables in OS, drive architecture and so on. For expample, some space is already allocated by Windows for page files, etc.  

No, I don't think there is a solid rule of thumb because it probably depends on your operating system, and also what you actually do with your computer. If you are having problems, then you might want to leave more space to see if it helps. But if you aren't then you shouldn't spend any time worrying about it.
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