Add a incomplete section on strong and weak scaling. Pictures are already there.

21_distributed-memory.tex

@@ -390,10 +390,32 @@ proper load balancings.
 Furthermore, we recommend that you use the a non-greedy load
 metric if you switch this feature on (\texttt{hotspot}, e.g.).
 
+\subsection{Weak and strong scaling}
 
- 
- 
+TODO
+
+\begin{figure}[h]
+\begin{center}
+  \includegraphics[width=0.5\textwidth]{sketches/strong-scaling-grid-223.pdf}
+\end{center} 
+\caption{%
+  A grid with $36^d$ cells on the coarse grid which allows to use $1$, $2^d$, $4^d$, and $12^d$ ranks
+  to uniformly distribute the load.
+}
+\end{figure}
 
+\begin{figure}[h]
+\begin{center}
+  \includegraphics[width=0.4\textwidth]{sketches/weak-scaling-1.pdf}\hspace{0.1cm}
+  \includegraphics[width=0.4\textwidth]{sketches/weak-scaling-2.pdf}
+  \\
+  \vspace{0.1cm}
+  \includegraphics[width=0.4\textwidth]{sketches/weak-scaling-4.pdf}\hspace{0.1cm}
+  \includegraphics[width=0.4\textwidth]{sketches/weak-scaling-8.pdf}
+\end{center} 
+\caption{Weak scaling experiment growing the domain by factors $1$, $2^d$, $4^d$, and $8^d$. \texttt{ranks\_per\_dimension} is chosen 1,2,4,8.}
+}
+\end{figure}
 
 \section{MPI troubleshooting and inefficiency patterns}
 \label{section:mpi:inefficiency-patterns}