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(1) [[latex2($$SpeedupOverall = \frac{Old~Execution~Time}{New~Execution~Time}$$)]] [[latex2($$SpeedupOverall = \frac{Old~Execution~Time}{New~Execution~Time}$$)]] (1)

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$$Speedup = \frac{Performance~using~enhancement~when~possible}{Performance~without~enhancement}$$

See SpeedUp

Notice that we are talking about the entire task here and that performance (speedup) is defined in terms of execution time! So we have to define the following:

latex2($$SpeedupOverall = \frac{Old~Execution~Time}{New~Execution~Time}$$) (1)

$$New~Exec~Time = Old~Exec~Time \left( 1 - FractionEnhanced + \frac{FractionEnhanced}{SpeedupEnhanced}\right)$$

or

                       Execution Time affected by Improvement
New Execution Time =   --------------------------------------  + Execution Time unaffected
                            Amount of Improvement (x times) 

So we have
                                     1
SpeedupOverall = --------------------------------------------
                                           FractionEnhanced
                 (1 - FractionEnhanced) + ------------------ )
                                           SpeedupEnhanced

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AmdahlsLaw (last edited 2020-01-23 23:15:20 by scot)