Overview of clone files, dataless files, sparse files, symbolic links, and firmlinks, and how used and free space is accounted for in APFS.
clone
We’re almost unaware of clone files, and how they’ve changed macOS. But look at most documents that have been saved more than once, and you’ll see they’ve now be cloned.
Understanding how APFS works: inodes, attributes, file extents, extended attributes, and how they change with editing and cloning.
Knowing a little about sparse and clone files in APFS is dangerous, as it can lead you to draw the wrong conclusions.
We even used to use it to defrag free space on a disk: clone the volume to another disk, and clone it back again. Why is cloning becoming so hard now?
How does copy on write work, and how do clones grow apart? What effect do they have on the use of space and performance?
Similarities and differences, how to make each in the Finder and Terminal, how much space they use, and how they work in APFS.
Save space on your storage and backups by removing all copies. But does it work if they’re APFS clone files? And does that housekeeping utility detect clones for you?
How APFS containers and volumes work. What hard links, clones and sparse files are, and when they break down.
You’re in control of a traditional file system, but with snapshots, clones, sparse files and other volumes sharing free space, APFS isn’t as simple.
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