The mailing list for listmasters using Sympa

["Michael L. Hitch" <address@concealed>]

What exactly is the avg parameter in sympa.conf supposed to do.  My 
interpretation of the description in the reference manual, "Maximum number 
of different Internet domains within addresses per sendmail call." would 
be that there should be up to 'nrcpt' recipients with no more that 'avg' 
differnet domains.  That is not what I was seeing happening.

  I was investigating a delay in sending to one of our larger lists a 
couple of weeks ago, and noticed that it had done 170 sessions (sendmail 
calls) for 2881 subscribers.  One of those sessions had only 15 
recipients, of which only 7 went to our @montana.edu MX hsots.  I had 
'nrcpts' set to 100 to match how our previous mailing list software had 
been configured, and was using the default for 'avg' of 10.

  When looking into how Sympa was building the list of recipients, I 
noticed a very recent fix for sorting a list's addresses by domain 
(primarily for the review page, but apparently also done when distributing 
a message to the list.  After applying that change, I could see a 
signficant improvement in the number of recipients per session, but it 
didn't seem to be doing as well as I thougt it should.

  Looking at how 'avg' was being used, I came to conclusion that it was 
actually the maximum number of recipients per session when the domain of 
the previous recipient was different from the current recipient.  An 
example might be if there were 10 recipients with domain A, followed by 
some number in domain B, the 'avg' value of 10 would mean Sympa would send 
off only the 10 recipients of domain A, and start a new session starting 
with domain B.  In the case  where I saw only 15 recipients in one 
session, and only 7 going to our primary servers, the incorrectly sorted 
list of recipients had a mixture of different domains in the 1st 9 
recipients, followed by several @montana.edu address, then a different 
domain which closed that session.

  Once I understood what the 'avg' parameter was actually doing, I changed 
it to match 'nrcpt' and now Sympa delivers in the minimum number of 
sendmail calls like I wanted it to.

  To properly implement the 'avg' parameter as I interpret the 
description, there should be a count of domains intialzed to 0 eash 
session, and incremented each time the domain changes from the previous 
recipient's domain.  My workaround does what I wanted, so I haven't tried 
to fix the code to do what I think it should be doing.

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Michael L. Hitch                        address@concealed
Operations Consulting,  Information Technology Center
Montana State University, Bozeman, MT     USA