While out walkies this morning, I decided it was time to re-train SpamAssassin.
And so, on this blazing hot afternoon, I've been running sa-learn on various large collections of mail, both spam and ham.
And hearing the CPU fan spool up as CPU usage on the server goes from near-idle to 80% or so, for the horribly long time it takes for the Perl scripts to munch through my vast mail archives and do all the processing.
(I really should be migrating the whole server mess to Linode, but that's not happening this month, nor next. And, once moved, it'll need training again, but maybe I'll manage to set it up properly this time so that auto-learn will work.)