The Speculative Execution Impact For A 4-Core POWER9

[Zan Lynx]

I've heard rumors that AMD is planning to use SMT-4 for the next generation of EPYC targeted for late 2020 or 2021.

If it is a good idea or not is entirely dependent on what the code is like. Tight mathematical computation is bad for SMT. Branch heavy database lookup loves it.

[smitty3268]

Trust me. If there were a lot of magic gains to be had from adding SMT4 and SMT8, Intel and AMD would have done it.
I'd much rather get performance up by other means and be done with the unpredictability of SMT once and for all.

Rumor is that Zen 3 will provide SMT4. Take that with a big grain of salt, obviously. The rumor is that the desktop parts might be limited to SMT3 because you need to carefully program to take advantage of SMT4+ in order to get gains. Server/TR would have SMT4.

[angrypie]

AMD is going to release a 64-core/128-thread TR in Q4 2019.

I guess it will suffice.

Those are only rumors for now but it won't surprise me if they actually release it. After all they will be selling 12- and 16-core CPUs for a mainstream platform, might as well ramp up core count on TR to twist the knife on Intel a little more.

[toxicdragon]

Hi, phoronix Any news on testing the Blackbird against e.g. current Intel and AMD systems? Really waiting for such a test (premium member writing)