On 4 Feb 1999 15:30:24 -0000, Russell Nelson wrote:
>If qmail's QMTP client coagulated recipients addressed to the same
>hostname (chasing down MXes take more bandwidth, as Dan has proven),
>then we could tell the Mark Crispins of the world, "So implement QMTP
>if you're that concerned about resources. QMTP takes less bandwidth,
>and can receive any number of recipients in a single message."
The problem is concurrency, i.e. qmail needs to know that a host does
QMTP before spawning qmail-remote:s for the other addresses to this
host. This might be done by sorting by host [and by doing smtproutes
before qmail-remote it could be batched even more]. For SMTP one would
_choose_ to send one message per recipient (to get VERP and avoid the
overhead of dealing with rejections from the remote MTA at the SMTP
dialog level), but for QMTP the polite recipient shuts up and takes it.
This could also save DNS lookups, since the lookup would be done only
once per message per host (not usually a big savings, but may be for a
MLM host).
That and a few smtproutes to QMTP smarthosts + ezmlm would make an
awesome "message distributer".
>I'd really like to see this in qmail 2.0. Anything I can do to help, Dan?
-Sincerely, Fred
(Frederik Lindberg, Infectious Diseases, WashU, St. Louis, MO, USA)
