Henri van den Bulk edited Problem 3.tex  over 9 years ago

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\subsection{Problem 3}  With a $s$ factor or 3.5 the memory performance increases to 50\% of the new latency or $CPU_time$. $CPU_{time}$.  Using absolute execution times, Amdahl's law is in terms of $L_{new}$, the execution time after an improvement; , $L_{memory}$ the execution time affected by the improvement; $s$, how many times faster the improved part runs, or its speedup; and $L_{unaffected}$, the execution time unaffected by the improvement. In these terms, Amdahl's Law states that: \begin{displaymath}{L_{new}=\frac{L_{memory}}{s} + L_{unaffected}}\end{displaymath}  If we assume that $L_{new} = 100$ then based on the given that the new memory latency is 50\%, then that would imply that $L_{unaffected} = 50$. Using these numbers in the Amdahl's law we get the following:  \begin{displaymath}{100=\frac{L_{memory}}{3.5} + 50}\end{displaymath}