Draft result filtering methodology section + expand wamr native call section

2026-09-12 15:24:39 +02:00
parent f52ab00652
commit 2d2cd43dc5
12 changed files with 45 additions and 9 deletions
@@ -94,6 +94,7 @@ where \(\mathbf{1}\{o_{c,b} = o\}\) is the indicator function, which equals one
  In terms of \Gls{fail}'s database, this corresponds to summing \code{t.time2 - t.time1 + 1} after joining the trace intervals to their \gls{pilot} results and grouping them by outcome.
  The join accounts for the individual injected bits, so no additional factor for the bit width is required in the sum.
 }
+\todo[inline]{Don't put this in a footnote, put it in controlling what data gets extracted from the experiments}

 Weighted outcome totals are reported separately for each fault category, execution mode and injection location (memory, registers or instruction-pointer).
 Outcome shares describe the composition of each variant's fault space, while absolute totals show differences in vulnerability caused by executaion duration and memory footprint.
@@ -6,4 +6,10 @@

 \section{Result Filtering}\label{sec:resultfiltering}

+To analyse specific facets of a system under fault-injection, parts of the observed outcomes and generated measures can be excluded from evaluations.
+Experiments in this thesis aim to characterize program behavior under transient fault conditions regarding its execution mode, so additional overhead caused by, e.g., \Gls{wamr} runtime components is included in the analysis.
+Overhead introduced solely by fault-injection instrumentation is excluded, it is an artifact of the measurement process.
+
+\todo[inline]{Depending on what I do in the evaluations, this needs expansion}
+
 \end{document}
@@ -71,9 +71,12 @@ To circumvent this, \Gls{wamr}'s native function invocation mechanism can be use

 This registration populates a lookup table that maps the native function pointers to their names, so that \Gls{aot} programs can call \Gls{wamr}'s internal \code{aot\_invoke\_native} and interpreted programs can call \code{wasm\_interp\_call\_func\_native} to invoke those functions.
 This indirection happens implicitly, on the application level no special steps need to be taken, functions can be called by their registered names.
-
 To be compatible with the native function registration mechanism, functions need to accept the \Gls{wasm} execution environment as an argument (see \autoref{lst:wamrnativefunctions}).

+It is important to consider that this native call mechanism introduces additional overhead that provides additional attack surface during fault-injection.
+The return from the \code{fail\_start\_trace} call, the entry into the \code{fail\_stop\_trace} call and the entireties of any other marker calls within the traced region are susceptible to faults unintended in the experiment design: the source code instrumentation should only steer the fault-injection process, not interact with the workload execution itself.
+How to counteract this limitation is described later, in \autoref{sec:resultfiltering} and \autoref{sec:resultextractionandqueries}.
+
 \subsubsection{Wasm Module Instantiation and Execution}\label{sssec:wamrmoduleexecution}

 To load the workload's \Gls{wasm} module and run it, a series of steps need to be executed:
@@ -85,12 +88,12 @@ To load the workload's \Gls{wasm} module and run it, a series of steps need to b
  \item Call the exported entry function (\code{wasm\_runtime\_call\_wasm})
 \end{enumerate}

-In this thesis, compiled \Gls{wasm} modules are converted to C-style arrays using \code{xxd} and embedded into the program's source text.
-This way, file access can be avoided and the module is loaded by simply passing a pointer to the correct function.
-A simplified module call sequence is shown in \autoref{lst:wamrmodulecall}.
-
 \begin{codeblock}[label=lst:wamrmodulecall]{Calling a \Gls{wasm} module from C.}{C++}
  \inputminted{cpp}{listings/wamrmodulecall.cpp}
 \end{codeblock}

+In this thesis, compiled \Gls{wasm} modules are converted to C-style arrays using \code{xxd} and embedded into the program's source text.
+This way, file access can be avoided and the module is loaded by simply passing a pointer to the correct function.
+A simplified module call sequence is shown in \autoref{lst:wamrmodulecall}.
+
 \end{document}
@@ -4,7 +4,7 @@

 \begin{document}

-\section{Controlling What Data Gets Extracted From The Experiments}
+\section{Result Extraction and Database Queries}\label{sec:resultextractionandqueries}

 \begin{itemize}
  \item What queries are run?
@@ -0,0 +1,10 @@
+%! TeX program = lualatex
+%! TeX root = ../../thesis.tex
+\documentclass[../../thesis.tex]{subfiles}
+
+\begin{document}
+
+% \addchap{Compilation Options}\label{ch:compilationoptions}
+\chapter{Compilation Options}\label{ch:compilationoptions}
+
+\end{document}
@@ -4,7 +4,7 @@

 \begin{document}

-% \addchap{Examples}\label{ch:examples}
+% \addchap{Experiment Results}\label{ch:experimentresults}
 \chapter{Experiment Results}\label{ch:experimentresults}

 \end{document}
@@ -55,10 +55,13 @@
 \appendix
 % \pagenumbering{Roman}

-\subfile{chapters/0A_results/0A_00_results.tex}
+\subfile{chapters/0A_compilation_options/0A_00_compilation_options.tex}
 \cleardoublepage%

-\subfile{chapters/0B_sanity/0B_00_sanity_checks.tex}
+\subfile{chapters/0B_results/0B_00_results.tex}
+\cleardoublepage%
+
+\subfile{chapters/0C_sanity/0C_00_sanity_checks.tex}
 \cleardoublepage%

 \end{document}
@@ -105,3 +105,16 @@ date,wordcount
 2026-09-12T13:27:44+02:00,10236
 2026-09-12T13:28:26+02:00,10237
 2026-09-12T13:58:35+02:00,10237
+2026-09-12T14:31:54+02:00,10252
+2026-09-12T14:32:24+02:00,10254
+2026-09-12T15:01:16+02:00,10317
+2026-09-12T15:01:42+02:00,10317
+2026-09-12T15:01:56+02:00,10315
+2026-09-12T15:02:10+02:00,10315
+2026-09-12T15:02:50+02:00,10315
+2026-09-12T15:06:17+02:00,10324
+2026-09-12T15:11:33+02:00,10397
+2026-09-12T15:15:52+02:00,10400
+2026-09-12T15:19:31+02:00,10407
+2026-09-12T15:22:01+02:00,10476
+2026-09-12T15:22:34+02:00,10510