Performance Equation

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The Performance Equation is a term used in computer science. It refers to the calculation of the performance or speed of a central processing unit (CPU).

Basically the Basic Performance Equation [BPE] is an equation with 3 parameters which are required for the calculation of "Basic Performance" of a given system.

It is given by;

                            T = (N*S)/R

Where

'T' is the processor time [Program Execution Time]required to execute a given program written in some high level language .The compiler generates a machine language object program corresponding to the source program.

'N' is the total number of steps required to complete program execution.'N' is the actual number of instruction executions,not necessarily equal to the total number of machine language instructions in the object program.Some instructions are executed more than others(loops) and some are not executed at all(conditions).

'S' is the average number of basic steps each instruction execution requires,where each basic step is completed in one clock cycle.We say average as each instruction contains a variable number of steps depending on the instruction.

'R' is the clock rate [ in cycles per second ]

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