Any suggestion on performance testing methods

[news.bna.bellsouth.net]

Have written a few things in perl using gethostbyaddress and
gethostbyname....
review the DNS module....does anyone have anything to offer?
thanks in advance,

John

PS this is peformance testing not zone validity or anything...I would like
to push a selective forwarder to the limits just to see what it can do same
for a internet cache box.