From another list:

To start: we use lftp for lots of large file transfer at XYZCorp -
pulling 1mb-10GB files via ftp, http, sftp, scp, etc. It generally works
well, but it consumes a lot of CPU. Should HTTP download really peg a
cpu core to 100%? That seems excessive to me. Happy to pay market rate
plus a few beers to anyone who can help us figure out if this can be
improved. We can provide a reusable sample and an environment that
demonstrates this behavior.

== End of message
This is on a Linux server. If you're interested, I'll introduce you to the author.

Chris