Use rsync to compare large directory trees

hugo@whynothugo.nl (Hugo Osvaldo Barrera) — Sun, 20 Sep 2026 01:14:13 +0200

I had to rewrite some large back-ups recently in order for restic to properly de-duplicate them. I checked that the re-written back-ups are identical to the original ones by comparing the entire directory trees of the mounted back-ups.

I had some doubts on whether diff -qr or rsync -acni --delete would be the best approach and did some benchmarks and tests using /usr (total: 3.2GB) which has a large mix of files and permissions.

Diff on WhyNotHugo (雨果)

Use rsync to compare large directory trees