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