network tuning and performance troubleshooting

[Bob McIsaac]

Problem: Browser status 'looking up address' for 10 seconds for any
 web page clicked. Slashdot takes almost a minute to load. But FTP
performance is good and running a shoutcast stream is no problem.
Sending mail via my ISP is slow.

Investigation: -  "sysctl -a  | grep net | less" shows a ton of variables
with values assigned. Ping of nameserver assigned by dhcp takes 0.5ms.
Ping of freebsd.org = 90ms. Nothing obvious in loader.conf or
rc.conf  (defaults).  /var/log/messages has only startup info.

Question: - How to solve this thorny performance problem?  -Bob-