The performance question about Triple-speed ethernet

Throughput and latency time are very different network properties, although they can be somehow related.

Think for example if your server would be located on the other side of Earth, roughly 20000km far.

Due to speed of light limitations, you will have at least a latency of about 130ms for every arp response. On the other hand, if you stream udp data and don't care of immediate acknowledge, you can achieve the same throughput as if your server and client would be in the same room.