Re: Route cache performance under stress

Ralph Doncaster wrote:

Initially I was looking for tulip cards but almost nobody is producing
them any more.  Almost a year ago I came across the following list, which
is why I went with the 3com (at the time it indicated rx/tx irqmit for the
3com, until I emailed the author that I found out it was tx only)
http://www.fefe.de/linuxeth/

If you want 4-port tulip NICs, I've had decent luck with the Phobox p430tx
NICs ($350 or so per NIC, so not cheap).  That said, the e1000s are definately
better as far as my own testing has been concerned.  (I'm doing packet pushing
& reception, no significant routing, though).

One waring about e1000's, make sure you have active airflow across the NICs
if you put two together.  Otherwise, buy a dual port NIC...it has a single
chip and you will have less cooling issues.

Ben

I had joined the vortex list last fall looking for some tips and that
didn't help much (other than telling me that the 3com wasn't the best
choice).  I've since bought a couple tg3 and a bunch of e1000 cards that
I'm planning to put into production.

Rob's test results seem to show that even if I replace my 3c905cx cards
with e1000's I'll still get killed with a 50kpps synflood with my current
CPU.  Upgrading to dual 2Ghz CPUs is not a preferred solution since I
can't do that in a 1U rack-mount box.  Yeah, I could probably do it with
water cooling, but that's not an option in a telco hotel like 151 Front
St. (Toronto).

A couple weeks ago I got one of my techs to test freeBSD/polling with full
routing tables on a 1Ghz celeron and 2 e1000 cards.  His testing seems to
suggest it will handle a 50kpps synflood DOS.  It would be nice if Linux
could do the same.

Despite the BSD bashing (to be expected on a Linux list, I guess), I will
be using BSD as well as Linux for core routing.  The plan is 1 linux
router and 1 bsd router each running zebra, connected to separate upstream
transit providers, running ibgp between them, and both advertising a
default route into OSPF.  Then if I get hit with a DOS that kills Linux,
the BSD box will have a much better chance of staying up than if I just
used a second Linux box for redundancy.  If the BSD boxes turn out to have
twice the performance of the linux boxes, it may be better for me to dump
linux for routing altogether. :-(

-Ralph

-- 
Ben Greear [off-list ref]       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear