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Benchmarks and price/performance are going to start getting confusing now that cloud providers are selling a mix of vCPUs where some are real cores, and some are hyperthreads. Amazon's Graviton instances are full cores. I expected that since ARM doesn't have hyperthreads. But now Google is selling EPYC full cores as vCPUs with Tau. I would guess that forces the other providers to follow suit.
If we’re lucky, we’ll end up where we need to be - performance per dollar.

But that’s probably a big “if”.

Performance is hard to measure as a scalar.
There are a few ARM CPUs that do SMT
True, but I suspect that the simpler instruction format makes it much easier to extract parallelism from a single thread than it is with x86's.
I was under the impression that was already the case with all Intel processors.
Terminology nit: s/hyperthread/SMT thread/ - HyperThreading is an Intel marketing name for their implementation of SMT.
actually only the tau instace type is marked as non smt. e2 use ht and smt.

tau is just a different more native workload.

I was curious about the Altra processor listed in the charts since I hadn't heard of it. It is an Arm processor and it is absolutely huge - even bigger than the Epyc chip. https://www.anandtech.com/show/16315/the-ampere-altra-review