New bandwidth curve

inc/7.simulation_results.tex

@@ -300,6 +300,54 @@ These tables also provide information about the simulation time of the different
 \label{fig:latency_ddr4}
 \end{figure}
 
+In order to compare not only the total average bandwidth, but also its behavior over time, all benchmarks were run consecutively on gem5 SE amd DRAMSys and plotted as a bandwidth-time diagram in Figure \ref{fig:data_bus_util}.
+
+\begin{figure}[!ht]
+\begin{center}
+\begin{tikzpicture}
+\begin{axis}[
+    width=\linewidth,
+    xlabel={Relative Simulation Time},
+    ylabel={Data Bus Utilization},
+    xmin=0, xmax=1,
+    ymin=0,
+    ytick={0,0.1,0.2,0.3},
+    legend style={
+        at={(current bounding box.south-|current axis.south)},
+        anchor=north,
+        legend columns=-1,
+        draw=none,
+        /tikz/every even column/.append style={column sep=0.5cm}
+    },
+    ymajorgrids=true,
+    grid style=dashed,
+]
+
+\addplot[mark=none, color=blue] table [x=T,y=B,col sep=comma] {dat/gem5.csv};
+
+\addplot[mark=none, color=red] table [x=T,y=B,col sep=comma] {dat/dramsys.csv};
+
+\legend{gem5 SE, DRAMSys}
+
+\end{axis}
+\end{tikzpicture}
+\end{center}
+\caption{Data bus utilization over the simulation time with DDR4-2400.}
+\label{fig:data_bus_util}
+\end{figure}
+
+Similar to the previous comparisons, the bandwidth on average of DRAMSys is marginally lower than gem5.
+Furthermore, an increased fluctuation around a bandwidth value can be observed.
+However, the overall time behavior is the same:
+The highest bandwidth value is reached at the beginning of the simulation and the bandwidth drops to a low plateau at the end of the simulation.
+
+The \revabbr{mean absolute percentage error}{MAPE} is used to evaluate the deviations of the two bandwidth curves.
+With the total number of data points $n$, the individual actual values $A_t$ and the individual forecasted values $F_t$, the measure is defined as follows:
+\begin{equation}
+MAPE=\frac{1}{n}\sum_{t=1}^{n}\bigg|\frac{A_t-F_t}{A_t}\bigg|
+\end{equation}
+For the bandwidth simulations, the resulting MAPE value is 22.3\%.
+
 \subsection{Comparison to Ramulator}
 
 In order to evaluate the new simulation frontend with a simulator that uses a similar approach, the benchmarks are compared with Ramulator in this section.