Mitigating garbage requests & other connexion attempts

I remember when I first purchased my domain name and linked it
to my fixed IP address, without having even published it anywhere yet,
my /var/www/logs/access.log was full of attackers' weird requests.

The same thing happens in /var/log/authlog even with a nonstandard
port for SSH forwarding. I suppose it would also be there in
/var/log/maillog would I have set an email server up, and in other
places.

I know Peter Hansteen has worked on the latter case:
https://nxdomain.no/~peter/effective_spam_and_malware_countermeasures.html
But I am left bare facing the excessive malicious activity on my
httpd(8) and sshd(8) services.

So here's my question : is there a preferred / good practice way on
OpenBSD to deflect attacker activity ? I'm not too worried about my
system being penetrated, although one is never too careful, but I am
regarding the workload this puts on my server and connexion.

Cheers
-- 
Sylvain Saboua
looking for a PDP-11