On these pages:
https://github.com/giampaolo/pyftpdlib
http://pythonhosted.org/pyftpdlib/benchmarks.html

pyftpdlib vs. vsftpd 2.3.5
300 concurrent clients (QUIT)
pyftpdlib 0.03 secs
vsftpd 0.01 secs
speedup +0.14x

But it looks like a slowdown of x3 to me.

Also, on this page:
https://github.com/giampaolo/pyftpdlib
pyftpdlib vs. vsftpd 2.3.5

The "vsftpd" column is mislabeled "proftpd".

What we Did

Hey, this isn't a bug, it's just something me and @polarina did and we had a lot of trouble doing but in the end I believe it's worth it and worth documenting. We are open to constructive criticism for what we did. I was learning how to use proftpd as I went along so i probably made some beginner mistakes.

We created a config and systemd units for a socket activated proftpd t

The authentication step that produces the link to follow in a browser to authenticate gdfa uses a callback URI. The port that it listens to seems to be random each time the service is started. Could that be standardized, or is there a way to predict what port it will listen to?