diff --git a/talks-public/2021-03-30-cergy/2020-03-30-cergy.org b/talks-public/2021-03-30-cergy/2020-03-30-cergy.org index e5b67bc..8cbb1ce 100644 --- a/talks-public/2021-03-30-cergy/2020-03-30-cergy.org +++ b/talks-public/2021-03-30-cergy/2020-03-30-cergy.org @@ -1,185 +1,185 @@ #+COLUMNS: %40ITEM %10BEAMER_env(Env) %9BEAMER_envargs(Env Args) %10BEAMER_act(Act) %4BEAMER_col(Col) %10BEAMER_extra(Extra) %8BEAMER_opt(Opt) #+TITLE: Software Heritage #+SUBTITLE: Analyzing the Global Graph of Public Software Development #+BEAMER_HEADER: \date[2021-03-30, CYU]{30 Mars 2021\\Lab. ETIS --- CY Cergy Paris Université\\ (online)\\[-2ex]} #+AUTHOR: Stefano Zacchiroli #+DATE: 30 March 2021 #+EMAIL: zack@upsilon.cc #+INCLUDE: "../../common/modules/prelude-toc.org" :minlevel 1 #+INCLUDE: "../../common/modules/169.org" #+BEAMER_HEADER: \institute[UParis \& Inria]{Université de Paris \& Inria --- {\tt zack@upsilon.cc, @zacchiro}} #+BEAMER_HEADER: \author{Stefano Zacchiroli} # Required by graph-compression.org module #+LATEX_HEADER_EXTRA: \usepackage{pdfpages} # Syntax highlighting setup #+LATEX_HEADER_EXTRA: \usepackage{minted} #+LaTeX_HEADER_EXTRA: \usemintedstyle{tango} #+LaTeX_HEADER_EXTRA: \newminted{sql}{fontsize=\scriptsize} #+name: setup-minted #+begin_src emacs-lisp :exports results :results silent (setq org-latex-listings 'minted) (setq org-latex-minted-options '(("fontsize" "\\scriptsize") ("linenos" ""))) (setq org-latex-to-pdf-process '("pdflatex -shell-escape -interaction nonstopmode -output-directory %o %f" "pdflatex -shell-escape -interaction nonstopmode -output-directory %o %f" "pdflatex -shell-escape -interaction nonstopmode -output-directory %o %f")) #+end_src # End syntax highlighting setup * About me :B_ignoreheading: :PROPERTIES: :BEAMER_env: ignoreheading :END: #+INCLUDE: "this/zack.org" :minlevel 2 * Software Heritage #+INCLUDE: "../../common/modules/swh-goals-oneslide-vertical.org::#goals" :minlevel 2 ** An international, non profit initiative :PROPERTIES: :CUSTOM_ID: support :END: *** Sharing the vision :B_block: :PROPERTIES: :CUSTOM_ID: endorsement :BEAMER_COL: .5 :BEAMER_env: block :END: #+LATEX: \begin{center}{\includegraphics[width=\extblockscale{.4\linewidth}]{unesco_logo_en_285}}\end{center} #+LATEX: \vspace{-0.8cm} #+LATEX: \begin{center}\vskip 1em \includegraphics[width=\extblockscale{1.4\linewidth}]{support.pdf}\end{center} #+latex:\mbox{}~~~~~~~\tiny\url{www.softwareheritage.org/support/testimonials} *** Donors, members, sponsors :B_block: :PROPERTIES: :CUSTOM_ID: sponsors :BEAMER_COL: .5 :BEAMER_env: block :END: #+LATEX: \begin{center}\includegraphics[width=\extblockscale{.4\linewidth}]{inria-logo-new}\end{center} #+LATEX: \begin{center} #+LATEX: \colorbox{white}{\includegraphics[width=\extblockscale{1.4\linewidth}]{sponsors.pdf}} #+latex:\mbox{}~~~~~~~\tiny\url{www.softwareheritage.org/support/sponsors} #+LATEX: \end{center} ** Status :B_ignoreheading: :PROPERTIES: :BEAMER_env: ignoreheading :END: #+INCLUDE: "../../common/modules/status-extended.org::#archivinggoals" :minlevel 2 #+INCLUDE: "../../common/modules/status-extended.org::#architecture" :minlevel 2 :only-contents t #+INCLUDE: "../../common/modules/status-extended.org::#merkletree" :minlevel 2 -#+INCLUDE: "../../common/modules/status-extended.org::#datamodel" :minlevel 2 :only-contents t +#+INCLUDE: "../../common/modules/data-model.org::#merklestruct" :minlevel 2 #+INCLUDE: "../../common/modules/status-extended.org::#dagdetailsmall" :minlevel 2 :only-contents t #+INCLUDE: "../../common/modules/status-extended.org::#archive" :minlevel 2 * Querying the archive ** Exploitation #+BEAMER: \LARGE \centering How do you query the Software Heritage archive? #+BEAMER: \Large \\ (on a budget) ** Use cases --- product needs e.g., for https://archive.softwareheritage.org *** Browsing - =ls= - =git log= (Linux kernel: 800K+ commits) *** Wayback machine - tarball - =git bundle= (Linux kernel: 7M+ nodes) *** Provenance tracking - commit provenance (one/all contexts) (note: requires backtracking) - origin provenance (one/all contexts) *** Note :B_ignoreheading: :PROPERTIES: :BEAMER_env: ignoreheading :END: Note: we therefore need both the direct Merkle DAG graph and its *transposed* ** Use cases --- research questions *** For the sake of it - local graph topology - connected component size - enabling question to identify the best approach (e.g., scale-up v. scale-out) to conduct large-scale analyses - any other emerging property *** Software Engineering topics - software provenance analysis at this scale is pretty much unexplored yet - industry frontier: increase granularity down to the individual line of code - replicate at this scale (famous) studies that have generally been conducted on (much) smaller version control system samples to confirm/refute their findings - ... #+INCLUDE: "../../common/modules/dataset.org::#main" :minlevel 2 :only-contents t #+INCLUDE: "../../common/modules/dataset.org::#morequery" :minlevel 2 :only-contents t ** Sample study --- 50 years of gender differnces in code contributions - start from the Software Heritage graph dataset - detect gender of author names using standard tooling (=gender-guesser=) # - caveat: how to identify /first/ name? - analyze both authors and commits over time, bucketing by commit timestamp #+BEAMER: \begin{center} \includegraphics[height=0.45\textheight]{this/commits-pie.pdf} \includegraphics[height=0.45\textheight]{this/ratio-female-authors.pdf} \\ \scriptsize total commits by author gender (left), ratio of active female commiters over time (right)\end{center} *** #+BEGIN_EXPORT latex \vspace{-1mm} \begin{thebibliography}{} \footnotesize \bibitem{Zacchiroli2021} Stefano Zacchiroli \newblock Gender Differences in Public Code Contributions: a 50-year Perspective \newblock IEEE Software, March/April 2021 \end{thebibliography} #+END_EXPORT ** Discussion - one /can/ query such a corpus SQL-style - but relational representation shows its limits at this scale - ...at least as deployed on commercial SQL offerings such as Athena - note: (naive) sharding is ineffective, due to the pseudo-random distribution of node identifiers - experiments with Google BigQuery are ongoing - (we broke it at the first import attempt..., due to very large arrays in directory entry tables) * Graph compression #+INCLUDE: "../../common/modules/graph-compression.org::#main" :minlevel 2 :only-contents t * Conclusion #+INCLUDE: "this/roadmap.org" :minlevel 2 ** Wrapping up #+latex: \vspace{-2mm} *** - Software Heritage archives all public source code as a huge Merkle DAG - Querying and analyzing it at scale (20/200 B nodes/edges) is an open problem - Gold mine of research leads in sw. eng., complex networks, big code, reproducibility #+latex: \vspace{-2mm} *** References #+latex: \vspace{-1mm} #+BEGIN_EXPORT latex \begin{thebibliography}{} \scriptsize \bibitem{Abramatic2018} Jean-François Abramatic, Roberto Di Cosmo, Stefano Zacchiroli \newblock Building the Universal Archive of Source Code \newblock Communications of the ACM, October 2018 \bibitem{Pietri2019} Antoine Pietri, Diomidis Spinellis, Stefano Zacchiroli \newblock The Software Heritage graph dataset: public software development under one roof \newblock MSR 2019: 16th Intl. Conf. on Mining Software Repositories. IEEE \bibitem{Boldi2020} Paolo Boldi, Antoine Pietri, Sebastiano Vigna, Stefano Zacchiroli \newblock Ultra-Large-Scale Repository Analysis via Graph Compression \newblock SANER 2020, 27th Intl. Conf. on Software Analysis, Evolution and Reengineering. IEEE \end{thebibliography} #+END_EXPORT *** Contacts Stefano Zacchiroli / [[https://upsilon.cc/~zack/][upsilon.cc]] / [[mailto:zack@upsilon.cc][zack@upsilon.cc]] / [[https://twitter.com/zacchiro][@zacchiro]] * Appendix :B_appendix: :PROPERTIES: :BEAMER_env: appendix :END: