Significant network latency when using ipfw and in-kernel NAT

[Ian Smith]

On Fri, 14 Sep 2012 09:12:27 -0500, Soren Dreijer wrote:

 > Can anybody confirm that disabling these other options (rxcsum,
 > txcsum, vlanmtu, vlanhwtag, vlanhwfilter, vlanhwtso) won't cause my
 > adapter to lose its connectivity? This is a server in production and
 > I'd rather not cause an outage if I can prevent it. :)

Fair question Soren.  I've configured no VLANs; out of my depth, again!

cheers, Ian

 > On Fri, Sep 14, 2012 at 12:00 AM, Ian Smith <smithi at nimnet.asn.au> wrote:
 > > 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
 >