This technical note is intended to help you tune your network drivers for increased performance or reduced memory footprint.
First, we need to talk about network driver interface hardware chips — ASICs — which are sometimes referred to as NICs (network interface controllers, or network interface chips).
At the risk of oversimplifying, we can categorize NICs into two groups: high-performance and low-performance. We aren't talking about the media bit rate (10, 100 or 1000 Mbit) but rather the ability of the complete system, when using the NIC, to avoid packet loss.
Hardware engineers work very hard to design media that rarely lose a packet. And there is a gain, or amplifying effect: when you lose 1% of your packets, you don't lose 1% of your throughput via a protocol, you lose around 50% of your throughput, due to the incurred software-level protocol timeouts and/or retransmissions.