# Amdahl's law

(a)

Illustrate Amdahl's law in terms of speedup vs. sequential portion of program by showing the speedup for N = 8 processors when the sequential portion of the program grows from 1% to 25%.

(b)

( Amdahl's law) With sequential execution occurring 15% of the time:

(i) What is the maximum speedup with an infinite number of processors?

(ii) How many processors are required to be within 20% of the maximum speedup?

(iii) How many processors are required to be within 2% of the maximum speedup?

https://brainmass.com/computer-science/theoretical-computer-science/amdahl-law-556193

#### Solution Preview

(a) Amdahl's law:

Speedup (Sn) = T(1)/T(n) == Time taken by one processor/Time take by n processors = 1/ (f + (1/n) (1-f))

Where f is the fraction which should be strictly sequential

For n=8 processors,

For f ...

#### Solution Summary

Two problems based on Amdahi's law are solved to related speedup, sequential part of a program, number of processors.