Clustering certainly has some advantages on low power cores but I wouldn't expect them to go with SMT on lower power cores. Adding SMT doesn't cost much die ar

Clustering certainly has some advantages on low power cores but I wouldn't expect them to go with SMT on lower power cores. Adding SMT doesn't cost much die area but it adds a ton of difficulty to validation. I'd say for little cores you're generally better off with more, smaller, SMT1 cores than fewer, larger SMT2 cores. Where SMT really shines on consumer workloads is that sometimes you only have a few threads, which is why you want it on your big cores. And as an aside, Zen actually has the exact same arrangement of gates in both the bigger and smaller configuration, the smaller one just uses a more consistently small transistor size while the larger one scales transistor size to fanout more aggressively. One place where clustering is being used right now is in Arm's new A510 where two cores share a FPU and L2 but not a front end like the Bulldozer. https://en.wikichip.org/wiki/arm_holdings/microarchitectures/cortex-a510 https://en.wikichip.org/wiki/arm_holdings/microarchitectures...