On Thu, Mar 27, 2014 at 08:48:17PM +0000, MV wrote:
> > It is a program! Not a fixed mapping. It receives a sender address,
> > and replies (with a possibly cached per-sender) answer which is
> > computed on a mostly-round-robin basis.
>
> If that's not asking too much, could you please provide me with a
> practical example or point me to where I could to find one?
A small socketmap or tcp table service that ignores the lookup key
and returns the next element of a circular list of values with each
lookup is surely just a few lines of custom code. As for how to
write a socketmap or tcp table driver in general, your Google skills
are likely not too dissimilar from mine.
In perl the core lookup function boils down to:
@choices = ( ... );
my $count = @choices;
my $next = 0;
sub lookup { return $choices[$next++ % $count]; }
which ignores the lookup key and returns the next choice. You have
many choices of languages to choose from, and ways to run this as
a network or unix-domain socket service.
> > Don't know what overhead you have in mind.
>
> The overhead caused by my crappy perl script and its IO ops... but
> this is irrelevant right now.
A tcp or unix-domain socket request-reply round-trip should be
quite fast.
> > Do you send a flood of separate messages each from the same sender?
>
> By sender, do you mean email address or just $mydomain ?
Full envelope sender address.
> If you mean sender=f...@mydomain.tld, then yes, most of the mail sent
> comes from a single email account and is sent to a great number of
> individual recipients.
If you have the same sender for many concurrent messages (not just
multiple recipients of a single message), then you would not use
the proposed cache, making the code simpler.
--
Viktor.
