I've never heard this weird qualification for the definition of "line rate" that it somehow requires minimum packet size, so I looked it up. The first three sources for a quoted big-g search all imply or directly state that it's the same as bandwidth:
Line rate does imply pps at the smallest sized frames in the context of networking equipment performance. Vendors use it extensively in their docs.
64B is the minimum frame size in Ethernet, including interframe gap and preamble its 84B on the wire. It is the same with Ethernet, Gigabit Ethernet and even 100Gbit Ethernet, that source is not correct.
No line rate does not "imply pps at the smallest sized frames."
Network hardware always quote PPS using the smallest sizes. And this makes sense for things like route and switch processors. Perhaps you are confusing that.
You should reread your link a little more carefully. From your link:
">However it is also important to make sure that the device has the capacity or the ability to switch/route as many packets as required to achieve wire rate performance."
The key phrase there is "as required." Almost nobody needs to sustain forwarding Ethernet frames with empty TCP segments or empty UDP datagrams in them. In fact many vendors will spec for an average size. Since packet size x PPS will give you your throughput, if the average packet size is larger you need much less PPS to achieve line rate.
Line rate doesn't imply small packets. But most userspace benchmarking uses 64B packets. That being said, the "imix" packet size, which is supposed to represent internet traffic, is around 500B.
There are numerous imix definitions floating around now, it really depends on who you ask. The more realistic ones define a pattern of different sized packets. And performance varies greatly depending on which imix flavour you use, which probably goes back to the earlier poster's 'dumpster fire' comment (although I don't know exactly what NPU generation they are referring to).
