I made tests with iperf, iperf3, ssh + pv + /dev/zero, copying files, and netcat (nc). Most of the tests are showing 940 Mbit/s, like expected, including netcat. But when I saw that actually for some of these tools, the cpu was a bottleneck, I moved to exposing multiple ports for netcat, and using up to 8 parallel connections. This increased the speed from 800 Mbit/s to over 3 Gbit/s. My router is a cheap one, Hub 3 from Virgin Media. The ethernet cables are of quality. Could this be real? Or could netcat be compressing by default? Thanks, Nicu
Actually indeed it is not real. I make the test again now and it is a bit under 1Gbit/s aggregated across connections, on average, as expected. Previously probably the time was not enough to show enough degradation of the speeds of previous connections as i was opening more and i incorrectly assumed that the connections will quickly stabilize to equal throughputs, which is not real either.
I did get 3 Gbit/s via a thunderbolt direct connection between computers. However it was 3 Gbit in one direction and 500 Mbit in the other.