I’m in the process of starting a proper backup solution however over the years I’ve had a few copy-paste home directory from different systems as a quick and dirty solution. Now I have to pay my technical debt and remove the duplicates. I’m looking for a deduplication tool.

  • accept a destination directory
  • source locations should be deleted after the operation
  • if files content is the same then delete the redundant copy
  • if files content is different, move and change the name to avoid name collision I tried doing it in nautilus but it does not look at the files content, only the file name. Eg if two photos have the same content but different name then it will also create a redundant copy.

Edit: Some comments suggested using btrfs’ feature duperemove. This will replace the same file content with points to the same location. This is not what I intend, I intend to remove the redundant files completely.

Edit 2: Another quite cool solution is to use hardlinks. It will replace all occurances of the same data with a hardlink. Then the redundant directories can be traversed and whatever is a link can be deleted. The remaining files will be unique. I’m not going for this myself as I don’t trust my self to write a bug free implementation.

  • deadbeef79000@lemmy.nz
    3·
    5 months ago

    I have exactly the same problem.

    I got as far as using fdupe to identify duplicates and delete the extras. It was slow.

    Thinking about some of the other comments… If you use a tool to create hardlinks first, then one could then traverse the entire tree and deleting a file if it has more than one hardlink. The two phases could be done piecemeal and are cancelable and restartable.

      • deadbeef79000@lemmy.nz
        1·
        5 months ago

        Backup backup backup! If you have btrfs them just take a snapshot first: instantly.

        One could do a non-destructive rename first. E.g. prepend deleteme. to the file name, sanity check it, then ‘rollback’ by renaming back without the prefix or commit and delete anything with the prefix.