--show takes forever to finish

I use the --show command to get a list of recovered passes and it won't end for almost 5 hours now
I don't understand why, if I do the matching myself outside of hashcat by creating dictionaries it takes less time.

the command I run is:
hashcat64 -m hashtype --show --username --outfile-format=2 "hashes.txt" -o outfile.txt

my file contains 1m rows.