Your post should be voted top, it's the most informative. I've spent the whole day scratching my head. The power8 confusion in many ways reminds me of the p4 netburst architecture, not architecturally in any way, but in the sense that "when they are good they are really good". But both by and large are not any great shakes.
yeah, sorry, it was just a quick test; I didn't even run any erlang besides building it from scratch, starting it up and seeing that BEAM recognized the right number of schedulers. It would be interesting to run a more comprehensive test suite than a single timing run, for sure.
Otherwise the x86 comes out looking a lot better -- lower 95th percentile, lower max, lower average.
(Modulo usual complaints about benchmark porn: single run, lack of standard deviation, unknown configuration differences etc etc).