Re: [Sqlgrey-users] Re: Values for throttling

[Michel B. <mi...@bo...>]

Le Vendredi 10 Juin 2005 17:22, Michael Storz a =E9crit :
> >
> > If we want to mix the count from domain_awl and the count from from_a=
wl,
> > then we would need to query both tables everytime, which could result=
 in
> > a performance loss, which would be annoying especially for big sites.=
..
>
> If you look carefully at the algorithm, then you see that we do not hav=
e
> to check both tables in every case:
>
>     my $threshold =3D connect_src_throttle -
>                     $self->count_src_domain_awl($cltid) *
>                     group_domain_level;
>
> If connect_src_throttle =3D=3D group_domain_level then 1 entry in domai=
n_awl
> is enough to circumvene throttling. Only if connect_src_throttle >
> group_domain_level you have to check from_awl in addition.

I have some objections to using this algorithm instead of the one that I =
had=20
proposed :

One entry in domain_awl IMHO "wheights more" that group_domain_level entr=
ies=20
in from_awl. For one entry in domain_awl is equivalent to "AT LEAST=20
group_domain_level entries (or more...) for the same host and same domain=
 in=20
from_awl".

For this reason, I had considered that one entry in domain_awl was enough=
 to=20
consider that a given host was well behaved and known enough to allow it =
to=20
bypass throttling.

If you use the algorithm you propose, let's say with a domain_group_level=
 of=20
10 and a throttling threshold of 20, and you have one MTA that sends mail=
 for=20
ONLY one domain, then this MTA will make it to domain_awl (and have only =
one=20
entry there even though this may correspond to thousands of different=20
senders), but with your algorithm this will never be enough and this MTA =
will=20
still remain "throttleable".

So I still think that we shouldn't mix a count of entries in from_awl and=
=20
domain_awl, as they don't have the same meaning, and should rather use my=
=20
algorithm : Stop throttling for an IP if it has at least 1 entry in=20
domain_awl, or >=3D throttling threshold in from_awl.


> BTW, we use the algorithm, which checks for the IP address in domain_aw=
l
> and from_awl, for the opposite direction and call it fast propagation.
> That means, if an IP address is from a well behaved MTA, then we accept
> the triple immediately. This eliminates the delay for forwarded emails,
> because most of the time a wellbehaved MTA has an entry in domain_awl. =
But
> this is done with the cost of polluting the from_awl, therefore we want
> the additional table for forwarding.

Hmmm... I'm not sure that I completely understand what you mean here...

--=20
Michel Bouissou <mi...@bo...> OpenPGP ID 0xDDE8AC6E