ROBERT G. HOWARD wrote:
> Interesting, if acrimonious, conversation going on here between you
> two, but I still don't understand the 2-3 day delays that some of us are
> experiencing.
> A couple of times each week I notice replies to a question in my inbox,
> without finding the question itself. Later in the day, the question may
> appear, along with additional answers thereto. How come?
Likely one of two reasons, probably the second.
The first (less likely) reason is that the mail machine
at autox is trying to connect to your mail hosting machine
at your ISP, but having trouble. Here is an example of
that from my personal machine (I run the same software
here for some lists that mjb runs this list on):
Sep 6 21:24:48 blackknight sendmail[27144]: LAA17609:
to=msg@ra.isisnet.com,murder@ra.isisnet.com, delay=4+10:13:48,
xdelay=00:00:01, mailer=smtp, relay=ra.isisnet.com.
[199.45.83.5], stat=Deferred: No route to host
Basically, that's one email trying to get delivered
to two people on the machine ra.isisnet.com. The
"delay=4+10:13:48" means that message has been
queued for 4 days, 10 hours... etc.
My mail machine has been trying every 15 minutes
to deliver that email, with no success. The actual
error is "no route to host", meaning my mail
machine can't find a way to ra.isisnet.com to
pass the mail along.
The more likely solution has to do with the way
majordomo/sendmail handle mailing lists.
When mgs gets a post, it spawns a sort of a
thread on their server. The autox server takes
the list of names on the mgs list (hundreds
of people) and starts delivering the mail
one by one.
It reads the first address, finds out where
their mail machine is, connects to that mail
machine, delivers the mail, and signs off. Then
it connects to the next machine, and does the
same thing, until it makes it to the end
of the hundreds-long list.
The out-of-order can happen because these
mail transactions are not instantaneous, sometimes
aborted, and so on. When all is well, one
mail delivery takes a second or so. Sometimes
the connection can drop, and it'll take 10
minutes or so before the attempt is aborted
and the next list is tried.
So lets say there are ten names on the list,
called "one@one.com", "two@two.com", "three@three.com",
and so on.
Let's say I post a message right now. It'll
spawn a thread that starts to deliver my message.
Let's say one@one.com gets his mail right
away, and replies. His message is received and
starts another thread delivering mail.
It now becomes sort of a race. If for some reason
the first thread has worse luck making mail
deliveries than the second one, it's not
impossible you could get one@one.com's reply
to my mail before you get my mail. Especially
if you are far down the list.
That's likely the mechanism. It's also the
reason you get your posts back to you
really quickly at 4am but not at noon. The
whole network is more available then, so
those 400 connections take no time compared
to business rush hours.
--
Trevor Boicey
Ottawa, Canada
tboicey@brit.ca
http://www.brit.ca/~tboicey/
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