So, just when did we get that 8:1 or 9:1 speedup without having the processor clocks run faster. IBM was doing speculative execution, branch prediction, out of

So, just when did we get that 8:1 or 9:1 speedup without having the processor clocks run faster. IBM was doing speculative execution, branch prediction, out of order execution, and vector instructions also in the 1990s. There were careful instruction level traces of the advantages and speedups. Of course, vector instructions are for special purpose code, e.g., the ubiquitous inner products in linear algebra, probability, and digital filtering, but 9:1 was on general purpose code. IIRC, the instruction traces didn't show 9:1 or anywhere near that.