duf is extremely slow compared to dfrs

[Dialga]

$ time duf
...
real    1m30.064s
user    0m0.005s
sys     0m0.000s
$ time dfrs
...
real    0m0.002s
user    0m0.000s
sys     0m0.002s

duf always takes 1m30(repeated runs) whereas https://github.com/anthraxx/dfrs is instantaneous.

[C0rn3j]

Can you still reproduce?

If so, what's it hanging on, anything in sudo journalctl -ef or if that gives nothing, see what it hangs on with strace?

[Dialga]

Can produce only under specific conditions, see the similar issue Canop/dysk#57 for more details.