ProFtpd on my server showed minor delays when logging in. A simple way to reduce this effect is to add the following options to the configuration file /etc/proftpd.conf: UseReverseDNS off, IdentLookups off, and ServerIdent off
Speeding up login to an FTP server running ProFtpd
Is your ProFtpd login slow? Find out how to easily speed up logging into the FTP server! Apply three key options in /etc/proftpd.conf.