> Here is an interesting array:
>
> INTEL P-60: 23.96 BMPS
> > 4 instructions. Why is it that my P100 spits out something like
> > 39.19 BogoMIPS and my P233MMX spits out 466.15 bogomips? I know
> > that the Pentium had some issue with this, being that a standard
> > 486 executed *that* particular loop faster.
> >
> > So, why such the HUGE difference?
I'm surprised no one has noted yet that the original pentiums had an
_awful_ branch prediction bug, they would predict which way a brach was
likely to occur, then go and act as if the brach were going the other
way!!!!
This was fixed in the MMX chips.
The difference sticks out like a sore thumb in a tight bogomips loop since
every 3 or 4 instructions the pentium guesses a branch wrong and all sorts
of things stall because of it.
Chris
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