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cycles per instruction

The average number of clock cycles a processor spends on each instruction of a program; lower is better.

Cycles per instruction (CPI) is total clock cycles divided by instructions executed for a given program on a given processor; it depends on the microarchitecture and on the program (its mix of instructions, branches and memory waits).

Examples

  • 1,000 instructions that take 1,500 cycles have a CPI of 1.5.

See also

performance equation microarchitecture
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