Comment by Veserv

Encryption is unlikely to be relevant. As I pointed out, doing it on any modern desktop CPU with no offload gets you 25-40 Gb/s, 6-10x faster than the benchmarked throughput. It is not the bottleneck unless it is being done horribly wrong or they do not have access to AES instructions.

“It is slow because it is being layered over QUIC.” Then why did you layer over a bottleneck that slows you down by 25x. Second of all, they did not used to do that and they still only got 1 Gb/s previously which is abysmal.

Third of all, you can achieve QUIC feature parity (minus encryption which will be your per-core bottleneck) at 50-100 Gb/s per core, so even that is just a function of using a slow protocol.

Finally, CPU class used in benchmarking is largely irrelevant because I am discussing 20x per-core performance bottlenecks. You would need to be benchmarking on a desktop CPU from 25 years ago to get that degree of single-core performance difference. We are talking iPhone 6, a decade old phone, territory for a efficient implementation to bottleneck on the processor at just 4 Gb/s.

But again, it is probably not a problem with their code. It is likely something else stupid happening on the network stack or protocol side of which they are merely a client.