...
Initial results for tests with this configuration (using the iPerf 2 tool) indicate that UDP testing is a more reliable assessment of the calibrated bit rate (after correcting for ETH, IP, and UDP header overhead, the values reported below are for protocol payloads of a single UDP stream or 3 TCP connections).
The value plotted for 3 TCP connections at 10000 Mbps uses no tc qdisc, just the 10GE links. A similar value was obtained for 5 TCP connections.
...
Here are some windows with netprobe in operation, showing results:
We have also conducted more tests investigating the effects of RT Delay on Measurement (an impairment which should only affect TCP, of course). This cross-section was conducted with a 1Gbps rate limit implemented in a Token bucket filter on the path to the iPerf 2 Server.