apfsmacos
Ok so I have a large folder on disk see the image below
You can see it says the size of the folder is 8.46GB however this is mostly source code, and I think file system will be using file compression under the hood. I'd expect this folder to compress very well, so my question is this. "How can I find out how much actual physical space this folder is using?"
Thanks
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there seem to be a lot of questions around disk images, esp. sparse bundles and none of the answers I found here provide easy solutions. You seem to have a few problems, I can help you with the first one (I ran into the same problem myself):
Reclaimed 0 bytes out of 265.2 GB possible
diskutil secureErase freespace 0 /Volumes/VolumeName
For this step to succeed, there must be enough space left on the main Volume where the sparse image lives (I found roughly the space reclaimable plus a few GB to be a reliable rule of thumb.)
Then you can unmount the image and compaction should succeed.
freespace 0 fills the empty space with zeroes, all other options of diskutil secureErase freespace write random garbage to disk so other files are not recoverable.
The rest of the commands should work fine now, at least for me they did...
I realise this question is old and you most likely have moved on, but maybe it's a help to someone...
Best Answer
You should go to the terminal and from the terminal cd to the folder you want to get the size of. Once there type:
du -h. The last number it prints is the directory size.