performance - Cycles/byte calculations -

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in crypto communities common measure algorithm performance in cycles/byte. question is, parameters in cpu architecture affecting number? except clockspeed ofcourse :)

two important factors are:

  1. the isa of cpu, or more how closely cpu instructions map operations need perform - if can perform given operation in 1 instruction 1 cpu requires 3 instructions on cpu first cpu probably faster. if have specific crypto instructions on cpu, or extensions such simd can leveraged, better.

  2. the instruction issue rate of cpu, i.e. how many instructions can issued per clock cycle


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