Note that 8-way SMT is the "big core", and I'm almost convinced that 8-SMT is more about licensing than actually scaling. By supporting 8 threads per core (and

Note that 8-way SMT is the "big core", and I'm almost convinced that 8-SMT is more about licensing than actually scaling. By supporting 8 threads per core (and doubling the size of the core), you get a 30-core system that supports 240-threads. That's a licensing hack: since most enterprise software is paid per-core. I don't think that's entirely fair: Massively multi-user transactional applications (read: databases) are right in the wheelhouse of POWER, and they're exactly the kind of applications that benefit most from SMT. Lots of opportunities for latency hiding as you're chasing pointers from indexes to data blocks.