COMPUTER SCIENCE AND ENGINEERING
COMPUTER ARCHITECTURE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Speedup is limited by parallel fraction of the program
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There are no any speedup limitation
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Speedup increase linearly with the number of used proccessors
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No correct answer
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Detailed explanation-1: -In computer programming, Amdahl’s law is that, in a program with parallel processing, a relatively few instruction s that have to be performed in sequence will have a limiting factor on program speedup such that adding more processor s may not make the program run faster.
Detailed explanation-2: -The theoretical speedup of the latency of the execution of a program as a function of the number of processors executing it, according to Amdahl’s law. The speedup is limited by the serial part of the program.
Detailed explanation-3: -A well-known limitation of Amdahl’s law is that it only applies in situation where the problem size is constant and the number of processors varies (strong scalability– a concept we already discussed in Section 1.1).
Detailed explanation-4: -Amdahl’s Law can be expressed in mathematically as follows − SpeedupMAX = 1/((1-p)+(p/s)) SpeedupMAX = maximum performance gain. s = performance gain factor of p after implement the enhancements. p = the part which performance needs to be improved.
Detailed explanation-5: -Amdahl’s Law states a limit on just how much faster a parallel program can run than a given sequential program for a problem of a fixed size.