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           AppBITS: Hyperspace Reclaims Space Used by Identical Files

   Adam Engst

   Is it weird that what I like most about the new space-reclamation app
   [1]Hyperspace is its [2]documentation? That's because Hyperspace comes
   from John Siracusa, perhaps best known for his exhaustive reviews of
   Mac OS X for Ars Technica. Even if you have no need for Hyperspace,
   reading its FAQ will teach you a lot about one of the core features of
   the standard macOS APFS filesystem.

   Unlike apps such as MacPaw's[3]Gemini, which search for and delete
   duplicates'often with some degree of intentional fuzziness'Hyperspace
   scans your drive for identical files and turns all but one into
   space-saving clones that occupy virtually no space. For example, if you
   have three identical copies of a 2 GB file, Hyperspace keeps one copy
   and converts the other two into space-saving clones that initially take
   up no additional space. If you later modify one of the clones, only
   then will it grow to the file's full size.

   Space-saving clones have been with us since the dawn of APFS, and you
   create one every time you use the Finder to duplicate a file. Unlike
   symlinks and hard links, which are ways of making the same file appear
   in multiple locations, space-saving clones are regular files. Changes
   made to one do not affect any others, although a changed clone
   immediately occupies all the space it didn't before the change.

   Another notable aspect of Hyperspace is its business model. The app is
   free to[4]download from the Mac App Store, and you can scan your drive
   to see how much space it can reclaim. Only if you want to reclaim space
   do you need to pay. Your choices are $9.99 to use it for a month,
   $19.99 for a year, or $49.99 for lifetime access. These are one-time
   purchases, though you can instead opt for a subscription at $9.99 per
   month or $19.99 per year'the only win there would seem to be not having
   to remember to purchase again.

   When I ran Hyperspace, it identified just 3.24 GB of potential savings
   in the 900 GB of data on my 1 TB drive. I am curious about which files
   on my drive are duplicates, but Hyperspace reserves that information
   for those who pay'sensibly enough, since you could manually create
   Finder duplicates to replicate its functionality. I'm not that curious,
   though I do wonder how I ended up with over 11,000 duplicate files
   created in some way other than through the Finder.

   

References

   Visible links
   1. https://hypercritical.co/hyperspace/
   2. https://hypercritical.co/hyperspace/#faq
   3. https://macpaw.com/gemini
   4. https://apps.apple.com/us/app/hyperspace-reclaim-disk-space/id6739505345?mt=12

   Hidden links:
   5. https://tidbits.com/uploads/2025/03/Hyperspace.png

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