Significant network latency when using ipfw and in-kernel NAT

[Ian Smith]

On Thu, 13 Sep 2012 12:37:23 -0500, Soren Dreijer wrote:
     [Luigi Rizzo wrote:]
 > > i'd start by disabling all accelerations (and jumobgrams)
 > > and then move on from the results to figure out where is the problem.
 > 
 > So, I went ahead and disabled TSO on ix0. That seemed to fix the
 > intermittent connection issues I had been experiencing with keeping an
 > XMPP connection alive to one of our internal boxes. It hasn't done
 > anything for the ICMPs or TCP traffic originating from the FreeBSD
 > box, of course.

Please show ifconfig for ix0 and ix1 again after disabling tso, 
rxcsum, txcsum, vlanmtu, vlanhwtag, vlanhwfilter, vlanhwtso
and any other configured accelerations, as Luigi recommended?

Then we'd know if your problem was related to any of that, or not.

cheers, Ian