On Sat, 2010-06-12 at 14:07 +0100, RW wrote:
> On Sat, 12 Jun 2010 13:06:23 +0200
> Karsten Bräckelmann <guent...@rudersport.de> wrote:
>
> > No need to stretch the term "large". That's a throughput of more than
> > 1 mail per second -- 100k SMTP connections per day. And that is
> > without any local caching at all. With caching, the throughput would
> > be considerably higher, before you ever cross the threshold and get on
> > their heavy-user radar.
>
> I think it's worth pointing-out that SA does deep-checking on zen to
> catch spammers in SBL that are relaying though other people's servers.
>
> If you reject on zen at the SMTP level you not only do fewer lookups,
> but you should also get a higher hit-rate at the DNS cache.
True -- just doesn't effect the math above. :)
For the numbers I used the "100k SMTP connections" limit for Spamhaus
free usage, rather than the "300k queries". So there's room left.
Pointing out deep-parsing for SBL is a good one, though. While there's a
single limit, there are multiple lists and query styles. PBL and XBL is
a single query per mail. SBL does deep-parsing, and DBL is RHS -- these
are most likely to result in more queries per mail. Without caching...
--
char *t="\10pse\0r\0dtu...@ghno\x4e\xc8\x79\xf4\xab\x51\x8a\x10\xf4\xf4\xc4";
main(){ char h,m=h=*t++,*x=t+2*h,c,i,l=*x,s=0; for (i=0;i<l;i++){ i%8? c<<=1:
(c=*++x); c&128 && (s+=h); if (!(h>>=1)||!t[s+h]){ putchar(t[s]);h=m;s=0; }}}
