03-fusing-kernels.tex

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\paragraph{Fusing Kernels}
The program has four kernels, that all access the same cells for a single instance of the kernel. They are: \texttt{propagate}, \texttt{rebound}, \texttt{collision}, and \texttt{av\_velocity}.  It would make sense to fuse these kernels together. This will reduce the number of times the same cell is fetched from memory. The speedup achieved by doing this is shown in Table~\ref{table:fusing-kernels}.

\begin{table}[ht]
\vspace{-3mm}
\centering
\caption{Runtimes after fusing the \texttt{propagate}, \texttt{rebound}, \texttt{collision} and \texttt{av\_velocity} kernels}
\vspace{1mm}
\begin{tabular}{|c||p{5.8em}|p{4.8em}|}
    \hline
    Size & Runtime (s) & Speedup \\
    \hline
    128x128 & 2.811 & 1.31x \\
    \hline
    256x256 & 8.811 & 1.75x \\
    \hline
    1024x1024 & 24.911 & 3.11x \\
    \hline
\end{tabular}
\label{table:fusing-kernels}
\vspace{-5mm}
\end{table}