What is the expected behaviour or performance when cloning a directory on apfs? In my brief experiments, I have found cloning a directory with a large number of small files slow.
In the guide it says "A clone is a nearly instantaneous copy of a file or directory...". While it is certainly instantaneous for a single file or a small directory, it doesnt seem to be true for something like the mail directory. I cloned my mail directory after copying it to a apfs partition and it took just under two minutes to clone 77000 files totaling under 2 gigabytes. Still faster than a duplicate under HFS+, but not nearly instant.
I assumed that performance would be similar regardless of number of files or size, given this is how other copy-on-write filesystems I have used functioned ie ZFS and it's contant time snapshots and clones.
I realize that it is very much early days and overall I think it is great that Apple is creating a new fs. Is this something which is expected to improve as time goes on or is it always likely to be slower to clone a large number of files?
Any information appreciated.
Celso.
