AMDAHL'S LAW and PARALLELISM

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In our discussion of the KELLY 3 machine (100 high-performance microprocessors with a sophisticated interconnection network), we argued that 100 processors, each capable of 1GFLOPS, could meet out target of 100 GFLOP.
Amdahl's law means that since we want

$\begin{displaymath}{\rm speedup}_{\rm overall} = 100 \end{displaymath}$

but we can at best apply parallelism to get

$\begin{displaymath}{\rm speedup}_{\rm enhanced} = 100 {\rm ~~(have~only~100~processors)} \end{displaymath}$

It follows that

$\begin{displaymath}{\rm fraction}_{\rm enhanced} = 100\% \end{displaymath}$
To get the full benefit of parallelism, the entire program must be parallelised