Significant network latency when using ipfw and in-kernel NAT

[Luigi Rizzo]

On Sun, Sep 16, 2012 at 10:39:36PM -0500, Soren Dreijer wrote:
> Some more updates:
> 
> I went ahead and disabled a few options on the ixgbe network interface
> today (most notably rxcsum and txcsum), which improved ping times to
> the FreeBSD box. I'm now able to reliably ping it with ~40ms from my
> house. TCP traffic in general also seems to be slightly "better" as I
> can actually 'wget google.com' now, although it's still horribly slow
> and takes maybe 20 seconds or so to download.
> 
> The ifconfig for the public adapter now looks like this:
> 
> ix1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
>         options=b8<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM>

what about the other one ? Also, please disable jumbo_mtu as well.
On both inside and outside.

Finally, can you send the output of
"ipfw show" and "ipfw pipe show" (anonymized if you like, but
please preserve the counters) to see if there is any traffic
that is looping ?

thanks
luigi

> 
> I'm running out of ideas of what to do here...
> 
> / Soren
>