LaTeX/Homework_Lesson_10.tex

@@ -32,71 +32,6 @@ Submit the source code and the screen shots of the standard output and the kerne
 \section{Code}%
 \label{sec:Code}
 
-\subsection{Custom Python Code}%
-\label{sub:Custom Python Code}
-The following code was written by me with the intend to measure the jitter in a python code.
-It uses the \textit{schedtool} program provided with the PREEMPT\_RT patches to schedule itself.
-\definecolor{mGreen}{rgb}{0,0.6,0}
-\definecolor{mGray}{rgb}{0.5,0.5,0.5}
-\definecolor{mPurple}{rgb}{0.58,0,0.82}
-\definecolor{backgroundColour}{rgb}{0.95,0.95,0.92}
-\lstset{
-    language=python,
-    backgroundcolor=\color{backgroundColour},   
-    commentstyle=\color{mGreen},
-    keywordstyle=\color{magenta},
-    numberstyle=\tiny\color{mGray},
-    stringstyle=\color{mPurple},
-    basicstyle=\ttfamily\scriptsize,
-    breakatwhitespace=false,         
-    breaklines=true,                 
-    captionpos=b,                    
-    keepspaces=true,                 
-    numbers=left,                    
-    firstnumber=0,
-    stepnumber=1,
-    numbersep=5pt,                  
-    showspaces=false,                
-    showstringspaces=false,
-    showtabs=false,                  
-    tabsize=2,
-    literate={~}{{$\mathtt{\sim}$}}1
-}
-\lstset{literate=%
-    {Ö}{{\"O}}1
-    {Ä}{{\"A}}1
-    {Ü}{{\"U}}1
-    {ß}{{\ss}}2
-    {ü}{{\"u}}1
-    {ä}{{\"a}}1
-    {ö}{{\"o}}1
-}
-\lstinputlisting{../test.py}
-\clearpage
-
-\subsubsection{Output}%
-\label{ssub:Python:Output}
-Unfortunately, as can be seen by the following output,
-the jitter isn't really affected by the activation or deactivation of the PREEMPT\_RT patches.
-
-\paragraph{with PREEMPT\_RT}%
-\label{par:Python:with PREEMPT RT}
-\begin{center}
-    \includegraphics[width = .75\textwidth]{with_preempt_rt.png}
-\end{center}
-
-\paragraph{without PREEMPT\_RT}%
-\label{par:Python:without PREEMPT RT}
-\begin{center}
-    \includegraphics[width = .75\textwidth]{no_preempt_rt.png}
-\end{center}
-\clearpage
-
-\subsection{Using Existing Programs}%
-\label{sub:Using Existing Programs}
-The following code is just a shell script that makes use of two programs provided by the \texttt{rt-tests} package (Arch Linux).
-It uses the \texttt{hackbench} program to put stress on the system and then evaluates the maximum latency with the \texttt{cyclictest} program.
-This provides a much more reliable method of testing the real-time capabilites of the system than any self-developed code I was able to come up with.
 \definecolor{mGreen}{rgb}{0,0.6,0}
 \definecolor{mGray}{rgb}{0.5,0.5,0.5}
 \definecolor{mPurple}{rgb}{0.58,0,0.82}
@@ -132,23 +67,24 @@ This provides a much more reliable method of testing the real-time capabilites o
     {ä}{{\"a}}1
     {ö}{{\"o}}1
 }
+
+The following code is just a shell script that makes use of two programs provided by the \texttt{rt-tests} package (Arch Linux).
+It uses the \texttt{hackbench} program to put stress on the system and then evaluates the maximum latency with the \texttt{cyclictest} program.
+This provides a much more reliable method of testing the real-time capabilites of the system than any self-developed code I was able to come up with.
 \lstinputlisting{../test.sh}
 The code is based on the following two sources:\\
 \url{https://wiki.archlinux.org/title/Realtime_kernel_patchset}\\
 \url{https://shuhaowu.com/blog/2022/02-linux-rt-appdev-part2.html}
 
-\subsubsection{Output}%
+\section{Output}%
-\label{ssub:BASH:Output}
+\label{sec:Output}
-The following output shows that while the PREEMPT\_RT patch doesn't really affect the average latency it drastically reduces the maximum latency.
 
-\paragraph{with PREEMPT\_RT}%
+\subsection{with PREEMPT\_RT}%
-\label{par:BASH:with PREEMPT RT}
+\label{sub:with PREEMPT RT}
-\mbox{}\\
 \includegraphics[width = \textwidth]{with_rt.png}
 
-\paragraph{without PREEMPT\_RT}%
+\subsection{without PREEMPT\_RT}%
-\label{par:BASH:without PREEMPT RT}
+\label{sub:without PREEMPT RT}
-\mbox{}\\
 \includegraphics[width = \textwidth]{without_rt.png}
 
 \end{document}

test.py

@@ -1,44 +0,0 @@
-import subprocess
-import time
-import matplotlib.pyplot as plt
-
-ITERATIONS = 300
-ITERATION_DURATION = 1 #second(s)
-
-def set_rt_priority():
-   subprocess.run(["schedtool", "-F", "-p", "99"], check=True)
-
-def rt_task():
-    new_time = time.time()
-    jitter_record = []
-
-    for i in range(ITERATIONS + 1):
-        old_time = new_time
-        new_time = time.time()
-
-        print("--------------------------------------------------")
-        print(f"system time:\t{new_time} s")
-        print(f"time diff:\t{new_time - old_time} s")
-
-        # jitter
-        jitter = new_time - old_time - ITERATION_DURATION
-        jitter_record.append(jitter)
-        print(f"jitter:\t{jitter} s")
-
-        # sleep for the rest of one second
-        time.sleep(new_time + ITERATION_DURATION - time.time())
-
-    #remove the first measurement
-    jitter_record.pop(0) 
-
-    #plot and store the jitter record
-    plt.plot(jitter_record)
-    plt.title(f"Jitter at {ITERATION_DURATION} s interval")
-    plt.xlabel("Iteration")
-    plt.ylabel("Jitter (in s)")
-    plt.savefig("out.svg")
-
-
-if __name__ == "__main__":
-    set_rt_priority()
-    rt_task()