The turbo curves depend on the exact type of Xeon. Were they Bronze or Silver? Those are much worse in that regard.
It is also unclear to me that AVX-512 is necessarily problematic in terms of power and thermal effects. Scalar code on many threads actually uses more energy (dispatch/control of OoO instructions being the main driver) than vector code (running far fewer instructions). The much-maligned power-up phase does not matter if running vector code for at least a millisecond.
I agree dedicated HW can be more power-efficient still, assuming it does exactly what your algorithm requires. And yet they make the fragmentation and deployment issues (can I use it?) of SIMD look trivial by comparison :)
Thanks for the data point. Water cooled, impressive.
But what is the problem here? Power is work per time. More power can be a good thing, especially if the work is useful. This is more likely in the SIMD case, which has much lower OoO cost than scalar code in terms of total work accomplished. At some point, the chip hits a limit and throttles. This means less speedup than otherwise might have been the case, but it's still a useful speedup relative to scalar, right?
It is also unclear to me that AVX-512 is necessarily problematic in terms of power and thermal effects. Scalar code on many threads actually uses more energy (dispatch/control of OoO instructions being the main driver) than vector code (running far fewer instructions). The much-maligned power-up phase does not matter if running vector code for at least a millisecond.
I agree dedicated HW can be more power-efficient still, assuming it does exactly what your algorithm requires. And yet they make the fragmentation and deployment issues (can I use it?) of SIMD look trivial by comparison :)