dummynet dropping too many packets

[rihad]

I'm so happy today: finally running a "ifp->if_snd.ifq_drv_maxlen = 
4096;" and HZ=4000 kernel with 4100+ online users @500+ mbps, and, most 
importantly, with absolutely 0 drops since boot time! ;-) Even if drops 
do come in, I'll know where to look first. I'd like to express my 
gratitude to Robert Watson for pointing out the "ifnet transmit queue 
sizes" issue, to others who suggested the problem might be in dummynet's 
burstiness, and yet to others who tried hard to help with other 
suggestions. Thank you, folks! Tomorrow I'm going to suggest to my boss 
to donate some $$$ to the FreeBSD Foundation: 
http://www.freebsdfoundation.org/donate/