source

The theoretical speedup in latency for task execution under fixed workloads as processors increase.

Where:

S = theoretical speedup of the execution of the whole task when enhancements are applied

p = proportion of the program that can be parallelized (0 ≤ p ≤ 1)

n = number of processors

(1−p) = proportion of the program that remains serial

The speedup is fundamentally limited by the serial (I/O) portion of the program.

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