On Wed, Mar 10, 2010 at 5:52 PM, Gregory Franks wrote: > Since they're running on one physical machine, and since there is no flow > control with UDP, unlike TCP, your transmitter is probably overrunning your > receiver resulting in dropped packets. > > I was chatting about this issue with a co-worker and he said the same thing. The problem I have with this theory is that TCP can pass 8 Gbits/s through the same buffers without overrunning. The 3 Gbit/s stream of stateless packets should be processed in the same fashion as the 8 Gbits/s of stateful. If fact, TCP transmissions are bursty in nature, which should place it at a higher risk of encountering overruns. Of course, all of this assumes that there isn't some sort of traffic shaping mechanism (ie. TC) in effect. Something else for the OP to consider.