[Iptablelog-users] Using Memoize to speed up DNS

[sgdailey <sgd...@ro...>]

Thanks to Michael Brown for pointing me in the right direction on the delay
I was experiencing in the web page updates. I have modified feed_db.pl a
little bit to use memoize to speed up name lookups. Memoize is a Perl module
and can be downloaded here.
http://perl.plover.com/Memoize/Memoize-1.01.tar.gz
Memoize will cache results of a function, next time that function is called
it will see if the arguments already have a cached result and if so will
simply use the cached results instead of calling the function again. Here
are the changes I made to feed_db.pl

line 30 or so looks like this:

use Socket;

just add these next three lines under that line:

use Memoize;
memoize 'mygethostbyaddr';
sub mygethostbyaddr { gethostbyaddr(@_) };

I haven't tested it extensively yet but I'm hoping it wont continuously look
up a host that has probed a thousand ports. I am about to flood the log and
see how it handles it. I will post results.

Thanks again to Michael Brown

sgdailey