> My first guess would be that some items on your internal drive are
> hardlinked, and that when you rsync, those items are being created on the
> external drive as separate files with each copy taking up space. And I can
> confirm by inspection that there are many hardlinked items inside the Xcode 9
> app, for example. There's a flag you can supply to rsync ("--hard-links") to
> tell it to detect and recreate hard links on the destination drive, which
> should eliminate this reason for the size difference.
Did not work. I erased Xcode again and rsync’ed it with —hard-links. Size
remains the same. 12 Gb instead of 7.8 local.
"S'il n'y a pas de solution, c'est qu'il n'y a pas de problème" (devise Shadok)
