Someone recently asked me what I thought was the most exciting thing about the new System z EC12 processor. My response came with no hesitation whatsoever.
The transactional-execution facility could very well be the greatest single advancement in multithread performance on System z ever. Every indication is that this new facility is performing beyond IBM's wildest expectations. The benchmarks I've seen so far have been extremely impressive.
Improvements to multithread performance are more important than ever right now given that single-thread performance on CMOS chips has (or nearly has) reached its architectural limit. Very soon, CMOS CPU 'cores' will get smaller, but not faster. If we can't go 'up' we must go 'out' and IBM is doing a great job of breaking down those barriers.
Keep up the good work, IBM!