The mailing list for listmasters using Sympa

[Adam Bernstein <address@concealed>]

> > certainly for testing purposes, but mostly because we saw (as expected) a
> > vastly increased CPU load from the unlimited DKIM signing.  So we're
> > not
>
> this is weird to me because we are basically doing unlimited dkim
> signing on all of our outbound mail that originates from our listserver,
> and we have quite a large number of messages going out constantly, and
> the dkim-filter process is hardly using any CPU at all (and yes, it is
> actually signing).

Ah -- this may be because we're also VERPing all outbound messages (in 
Postfix, not Sympa), which means a separate message for every recipient, no 
batch sending.  So we end up doing maybe 10x the work or more on large 
lists with lots of recipients at eg. Yahoo or GMail, but it's worth it for 
various benefits, especially scrubbing addresses that come back from spam 
reporter feedback loops at AOL and other ISPs.  I'm guessing you're not 
doing the VERP?

If you are, then we should look at that milter implementation for sure....

(And before anybody mentions it, yes, the Postfix VERP alters the 
Return-Path on the way out, which might seem to be related to the problem 
I'm having with DKIM complaining that the message has been altered.  But 
that header is not part of the signing, and we even tested with VERP 
disabled, with no effect.)

     adam