Adam,
You nailed it,
Actually very few line-cards or fabric-less boxes with (run to completion
vendor chips) out there do line-rate at 64B packets nowadays.
-with the advent of 100G the "line-rate at 64B" is pretty much not a thing
anymore...
Something to consider, not because one wants to push 64B packets at
line-rate on all ports but because one needs to push IMIX through QOS or
filters... and the card/box might simply not deliver.
But those are two completely different use cases.
The fact that vendors (full disclosure - I work for Cisco) don’t want to
optimize for 64 bytes forwarding is totally independent on how those
architectures deal/manage to apply policies on the traffic.
64B traffic simply doesn’t happen apart from DDoS scenarios, so
why bother at all? Customers anyway want to use dedicated
anty-DDoS boxes, so apart from synthetic performance testing,
pushing the architecture to be able to forward couple of mpps more
just to cover the “64B” scenario means $ (sometimes $$$) just
to satisfy requirement that’s usually simply not there.
In other words, the fact that given architecture can’t forward "wire-rate"
of 64B traffic doesn’t mean that it can’t apply QoS for IMIX pattern
at wire-speed. Forwarding engine is usually different part of
hardware than services, more often than not decisions are totally
independent to speed up processing.
--
Łukasz Bromirski
CCIE R&S/SP #15929, CCDE #2012::17, PGP Key ID: 0xFD077F6A