6.x, 4.x ipfw/dummynet pf/altq - network performance issues

[Mike Tancsa]

On Mon, 05 Feb 2007 14:03:41 -0800, in sentex.lists.freebsd.questions
you wrote:

>
> I suppose my concerns are two-fold. Why is 6.x collapsing under traffic 
>that 4.11 could easily block and run merrily along with, and is there a 
>queueing mechanism in place that doesn't tie up the box so much on 
>inbound flows that it ignores all other relevant traffic?
>
>(as a note, all tests were done with device polling enabled. Without it 
>systems fall over pretty quickly. I also tried tests using 3com cards 
>and had the same results)


On the 6.x box, try enabling adding to /etc/sysctl.conf

kern.polling.enable=1
net.inet.ip.fastforwarding=1
kern.polling.idle_poll=1
kern.random.sys.harvest.ethernet=0

and in /boot/loader.conf, add

kern.hz="2000" 

Also removing 

options         ADAPTIVE_GIANT          # Giant mutex is adaptive.

from the kernel helps a bit as well.

with 
kern.polling.idle_poll=1

your load avg will be messed up but it should help performance a bit.

As for firewall rules, things really seem to fall down performance
wise, as compared to RELENG_4.  I havent found a way to improve that
performance.... However, on the plus side, an extra core does seem to
help a bit with the box remaining responsive.  For NICs, stay with em
or bge nics for now in RELENG_6

I have some misc test results at http://www.tancsa.com/blast.html

	---Mike
--------------------------------------------------------
Mike Tancsa, Sentex communications http://www.sentex.net
Providing Internet Access since 1994
mike at sentex.net, (http://www.tancsa.com)