Re: ISPmail Lenny tutorial ready

[emilio brambilla <emilio@antispam.it>]

hello,

Thomas Goirand wrote:

> ANY database server (even PostgreSQL) will be a lot slower if connecting
> to it using network. It's always better to use a Unix socket if
> possible. If you are using more than one db server, that's for
> redundancy, not for speed.

I cannot agree with this!

excluding particular use of the db (maybe tons of new connection per
second with very very very simple test query inside?) the network
latency is trascurable when compared with the query execution time
(which involves cpu, memory, disks)... if you have any benchmark stating
I'm wrong I can reconsider my opinion, but my data says network is not
an issue (ie the performance difference between unix socket and tcp
socket is less than 1%, even with slow 100 mbit/s networing).

I have some installations where the load balancer in front of the mysql
servers is there only to let the db scale up the performance (in effect,
if I only need redundancy I use heartbeat in active-standby cluster, not
a loadbalancer)

going back to the topic, I think Christoph did a great work with the
tutorial!

PS do someone have some *recent* benchmark test on greylisting? I tested
it a few years ago (say end of 2007) and it was very very efficient
against spam (ethically it was bad, as it uses remote server resources
to limit spam on local server, but on the antispam performance side it
was very nice);
now the sensation is that spammers learned the lesson of greylisting,
and greylisting does not block anything... I'm right or wrong with this
idea?


-- 
bye,
emilio