[Mailman-Users] Prioritizing mails?

[Mark Sapiro]

On 10/18/18 1:01 AM, Ralf Hildebrandt wrote:
> 
> This caused all other mail via Mailman to be more or less stalled. Is
> there a way of assigning priorities to lists, like giving all lists
> "normal" priority and large lists "low" priority?
> 
> OTOH sending small mails to large lists is ok, so maybe the product of
> "size_of_mail" and "number_of_list_recipients" could be used to adjust
> the priority accordingly....


The architecture of both Mailman 2.1 and Mailman 3 doesn't really allow
for this to be done too easily. Messages are queued for delivery in a
FIFO queue for the outgoing runner(s). Slicing the queue space into
multiple ranges for multiple runners doesn't solve the problem as other
messages in the range with the "big" message will still have to wait.

What could be done is to create multiple outgoing queues, say normal_out
and big_out and then have separate instances of the outgoing runner
processing the two queues. Then the handler that queues outgoing
messages could decide which queue based on whatever criteria are desired.

This wouldn't make the "big" message wait until after the normal
messages were all processed, but the "big" message would be processed by
a separate process and the normal messages wouldn't have to wait for it
to complete.

I don't think it would be too difficult to implement this, but my advice
would be to use content filtering and maximum message size to prevent
the problem which could have been easily avoided in this case by making
the attachment web accessible and including only a link in the post.

Note that if your list owners don't understand the importance of maximum
message size, there is for Mailman 2.1 an example handler that
implements a global maximum at
<https://www.msapiro.net/scripts/GlobalTooBig.py>.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan