apt-transport-http
apt-transport-https
both say
The used bandwidth can be limited with Acquire::http::Dl-Limit which
accepts integer values in kilobytes per second. The default value is 0
which deactivates the limit and tries to use all available bandwidth.
Note that this option implicitly disables downloading from multiple
servers at the same time.
That's great. Except when there is a mixture of http and https sources.
(Probably not considered back when there was only http.)
Then to achieve a Dl-Limit=8 we need to do e.g.,