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Something is constantly eating my hard disk space.

This pattern happens very often:

  • I free some space by deleting stuff (5-8 GB)
  • In about half an hour I have 0 (zero) free space

I have not downloaded anything.

I suspected that it is Google Chrome which eats my space because once when I cleared the cache and quit the browser it freed around 1GB of space. But this happened only once. After that clearing cache and quitting Google Chrome doesn't do much.

Last night I left my computer with free 7GB of space. When I wakened it (I do not turn off my computer – only close the lid) this morning there was 100MB left which very quickly became 0 (zero). Clearing cache and quitting Google Chrome just freed 20-30MB. When I log off and log on, the system freed 6,7GB.

I am not interested in solutions like:

  • restart the computer or log off
  • delete files

because I am constantly being deleting files and restarting the computer in order to find free space.

I suspect that there is a process or service that is constantly writing on my hard drive but it is triggered on some conditions. For example

How to find what application or process is constantly writing on my hard drive?

marked as duplicate by bmike osx Nov 12 '15 at 11:25

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7GB is low, too low. Only OS X needs a free space of 9GB for itself (and on a SSD you need even more free space, for the Garbage Collection).

Emptying caches does not help because they will be filled again. Apple OS X clears the caches on its own so there is no gain if you do it also. Chrome needs caches as does Safari, there is not much difference. Safari has better security.

Your problem can only be solved by freeing up more space definitively (moving a music or movies library for example to a second disk).

  • 4
    Please add why OS X needs 9 GB for itself? – klanomath Nov 2 '15 at 8:36

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