SMT Remains Very Advantageous For 5th Gen AMD EPYC Performance
The workload that benefited the most from SMT on the AMD EPYC 9575F 1P Supermicro server was 7-Zip compression going up by 61% with SMT enabled as it is by default. 7-Zip and a number of other compression workloads tend to scale really well with SMT/HT support.
When SMT enabled there ended up being a slight increase in power use over when SMT was disabled: 302 vs. 320 Watts while both peaked right at the 400 Watt TDP of the EPYC 9575F.
A 5% power increase on average is a small price for a 61% advantage with SMT in 7-Zip.
7-Zip Temp
The slight power increase isn't enough to adversely affect the thermals.
Another real-world workload benefiting the most from SMT on AMD EPYC Turin after 7-Zip was Intel's Embree ray-tracing kernels that is part of the oneAPI Rendering Toolkit. Solid improvements across the board with Embree when SMT was utilizing on this EPYC 9575F server. Very small power increase for huge performance gains.
The OpenMP-threaded John The Ripper password cracking/crypto software also benefits a lot from Zen 5's SMT support.