Hi Eric,

On Mon, Apr 25, 2011 at 5:38 PM, Eric Dumazet [off-list ref] wrote:

Since you have at sender a rule to spoof destination address of packets,
you should make sure you dont send "super packets (up to 64Kbytes)",
because it would stress the multipath more than you wanted to. This way,
you send only normal packets (1500 MTU).

ethtool -K eth0 tso off
ethtool -K eth0 gso off

I am pretty sure it should help your (atypic) workload.

I made new experiments with the exact same multipath setup as before,
but disabled TSO and GSO on all involved Ethernet interfaces. However,
this did not seem to change much about TCP's behavior when packets are
striped over heterogeneous paths. You can see the results of four
20-minute experiments on this plot:

http://home.simula.no/~kaspar/static/mptcp-emu-wlan-hspa-01-tos0.png

Cheers,
Dominik