\nonstopmode \documentclass[aspectratio=169,xcolor={svgnames}]{beamer} \usepackage[utf8]{inputenc} % \usepackage[frenchb]{babel} \usepackage{amsmath} \usepackage{mathtools} \usepackage{breqn} \usepackage{multirow} \usetheme{boxes} \usepackage{graphicx} \usepackage{import} \usepackage{adjustbox} \usepackage[absolute,overlay]{textpos} %\useoutertheme[footline=authortitle,subsection=false]{miniframes} %\useoutertheme[footline=authorinstitute,subsection=false]{miniframes} \useoutertheme{infolines} \setbeamertemplate{headline}{} \beamertemplatenavigationsymbolsempty \definecolor{TitleOrange}{RGB}{255,137,0} \setbeamercolor{title}{fg=TitleOrange} \setbeamercolor{frametitle}{fg=TitleOrange} \definecolor{ListOrange}{RGB}{255,145,5} \setbeamertemplate{itemize item}{\color{ListOrange}$\blacktriangleright$} \definecolor{verygrey}{RGB}{70,70,70} \setbeamercolor{normal text}{fg=verygrey} \usepackage{tabu} \usepackage{multicol} \usepackage{vwcol} \usepackage{stmaryrd} \usepackage{graphicx} \usepackage[normalem]{ulem} \AtBeginSection[]{ \begin{frame} \vfill \centering \begin{beamercolorbox}[sep=8pt,center,shadow=true,rounded=true]{title} \usebeamerfont{title}\insertsectionhead\par% \end{beamercolorbox} \vfill \end{frame} } \title{Garage, the low-tech storage platform for geo-distributed clusters} \author{Alex Auvolat, Deuxfleurs} \date{FOSDEM'24, 2024-02-03} \begin{document} \begin{frame} \centering \includegraphics[width=.3\linewidth]{../../sticker/Garage.png} \vspace{1em} {\large\bf Alex Auvolat, Deuxfleurs Association} \vspace{1em} \url{https://garagehq.deuxfleurs.fr/} Matrix channel: \texttt{\#garage:deuxfleurs.fr} \end{frame} \begin{frame} \frametitle{Who I am} \begin{columns}[t] \begin{column}{.2\textwidth} \centering \adjincludegraphics[width=.4\linewidth, valign=t]{../assets/alex.jpg} \end{column} \begin{column}{.6\textwidth} \textbf{Alex Auvolat}\\ PhD; co-founder of Deuxfleurs \end{column} \begin{column}{.2\textwidth} ~ \end{column} \end{columns} \vspace{2em} \begin{columns}[t] \begin{column}{.2\textwidth} \centering \adjincludegraphics[width=.5\linewidth, valign=t]{../assets/logos/deuxfleurs.pdf} \end{column} \begin{column}{.6\textwidth} \textbf{Deuxfleurs}\\ A non-profit self-hosting collective,\\ member of the CHATONS network \end{column} \begin{column}{.2\textwidth} \centering \adjincludegraphics[width=.7\linewidth, valign=t]{../assets/logos/logo_chatons.png} \end{column} \end{columns} \end{frame} \begin{frame} \frametitle{Our objective at Deuxfleurs} \begin{center} \textbf{Promote self-hosting and small-scale hosting\\ as an alternative to large cloud providers} \end{center} \vspace{2em} \visible<2->{ Why is it hard? } \visible<3->{ \vspace{2em} \begin{center} \textbf{\underline{Resilience}}\\ {\footnotesize we want good uptime/availability with low supervision} \end{center} } \end{frame} \begin{frame} \frametitle{Building a resilient system with cheap stuff} \only<1,4-7>{ \begin{itemize} \item \textcolor<5->{gray}{Commodity hardware (e.g. old desktop PCs)\\ \vspace{.5em} \visible<4->{{\footnotesize (can die at any time)}}} \vspace{1.5em} \item<5-> \textcolor<7->{gray}{Regular Internet (e.g. FTTB, FTTH) and power grid connections\\ \vspace{.5em} \visible<6->{{\footnotesize (can be unavailable randomly)}}} \vspace{1.5em} \item<7-> \textbf{Geographical redundancy} (multi-site replication) \end{itemize} } \only<2>{ \begin{center} \includegraphics[width=.8\linewidth]{../assets/neptune.jpg} \end{center} } \only<3>{ \begin{center} \includegraphics[width=.8\linewidth]{../assets/atuin.jpg} \end{center} } \only<8>{ \begin{center} \includegraphics[width=.8\linewidth]{../assets/inframap_jdll2023.pdf} \end{center} } \end{frame} \begin{frame} \frametitle{Object storage: a crucial component} \begin{center} \includegraphics[height=6em]{../assets/logos/Amazon-S3.jpg} \hspace{3em} \visible<2->{\includegraphics[height=5em]{../assets/logos/minio.png}} \hspace{3em} \visible<3>{\includegraphics[height=6em]{../../logo/garage_hires_crop.png}} \end{center} \vspace{1em} S3: a de-facto standard, many compatible applications \vspace{1em} \visible<2->{MinIO is self-hostable but not suited for geo-distributed deployments} \vspace{1em} \visible<3->{\textbf{Garage is a self-hosted drop-in replacement for the Amazon S3 object store}} \end{frame} \begin{frame} \frametitle{CRDTs / weak consistency instead of consensus} \underline{Internally, Garage uses only CRDTs} (conflict-free replicated data types) \vspace{2em} Why not Raft, Paxos, ...? Issues of consensus algorithms: \vspace{1em} \begin{itemize} \item<2-> \textbf{Software complexity} \vspace{1em} \item<3-> \textbf{Performance issues:} \vspace{.5em} \begin{itemize} \item<4-> The leader is a \textbf{bottleneck} for all requests\\ \vspace{.5em} \item<5-> \textbf{Sensitive to higher latency} between nodes \vspace{.5em} \item<6-> \textbf{Takes time to reconverge} when disrupted (e.g. node going down) \end{itemize} \end{itemize} \end{frame} \begin{frame} \frametitle{The data model of object storage} Object storage is basically a \textbf{key-value store}: \vspace{.5em} {\scriptsize \begin{center} \begin{tabular}{|l|p{7cm}|} \hline \textbf{Key: file path + name} & \textbf{Value: file data + metadata} \\ \hline \hline \texttt{index.html} & \texttt{Content-Type: text/html; charset=utf-8} \newline \texttt{Content-Length: 24929} \newline \texttt{} \\ \hline \texttt{img/logo.svg} & \texttt{Content-Type: text/svg+xml} \newline \texttt{Content-Length: 13429} \newline \texttt{} \\ \hline \texttt{download/index.html} & \texttt{Content-Type: text/html; charset=utf-8} \newline \texttt{Content-Length: 26563} \newline \texttt{} \\ \hline \end{tabular} \end{center} } \vspace{1em} \begin{itemize} \item<2> Maps well to CRDT data types \end{itemize} \end{frame} \begin{frame} \frametitle{Performance gains in practice} \begin{center} \includegraphics[width=.8\linewidth]{../assets/perf/endpoint_latency_0.7_0.8_minio.png} \end{center} \end{frame} % ======================================== TIMELINE % ======================================== TIMELINE % ======================================== TIMELINE \section{Recent developments} % ====================== v0.7.0 =============================== \begin{frame} \begin{center} \includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf} \end{center} \end{frame} \begin{frame} \frametitle{April 2022 - Garage v0.7.0} Focus on \underline{observability and ecosystem integration} \vspace{2em} \begin{itemize} \item \textbf{Monitoring:} metrics and traces, using OpenTelemetry \vspace{1em} \item Replication modes with 1 or 2 copies / weaker consistency \vspace{1em} \item Kubernetes integration for node discovery \vspace{1em} \item Admin API (v0.7.2) \end{itemize} \end{frame} \begin{frame} \frametitle{Metrics (Prometheus + Grafana)} \begin{center} \includegraphics[width=.9\linewidth]{../assets/screenshots/grafana_dashboard.png} \end{center} \end{frame} \begin{frame} \frametitle{Traces (Jaeger)} \begin{center} \includegraphics[width=.8\linewidth]{../assets/screenshots/jaeger_listobjects.png} \end{center} \end{frame} % ====================== v0.8.0 =============================== \begin{frame} \begin{center} \includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf} \end{center} \end{frame} \begin{frame} \frametitle{November 2022 - Garage v0.8.0} Focus on \underline{performance} \vspace{2em} \begin{itemize} \item \textbf{Alternative metadata DB engines} (LMDB, Sqlite) \vspace{1em} \item \textbf{Performance improvements:} block streaming, various optimizations... \vspace{1em} \item Bucket quotas (max size, max \#objects) \vspace{1em} \item Quality of life improvements, observability, etc. \end{itemize} \end{frame} \begin{frame} \frametitle{About metadata DB engines} \textbf{Issues with Sled:} \vspace{1em} \begin{itemize} \item Huge files on disk \vspace{.5em} \item Unpredictable performance, especially on HDD \vspace{.5em} \item API limitations \vspace{.5em} \item Not actively maintained \end{itemize} \vspace{2em} \textbf{LMDB:} very stable, good performance, file size is reasonable\\ \textbf{Sqlite} also available as a second choice \vspace{1em} Sled will be removed in Garage v1.0 \end{frame} \begin{frame} \frametitle{DB engine performance comparison} \begin{center} \includegraphics[width=.6\linewidth]{../assets/perf/db_engine.png} \end{center} NB: Sqlite was slow due to synchronous mode, now configurable \end{frame} \begin{frame} \frametitle{Block streaming} \begin{center} \only<1>{\includegraphics[width=.8\linewidth]{../assets/schema-streaming-1.png}} \only<2>{\includegraphics[width=.8\linewidth]{../assets/schema-streaming-2.png}} \end{center} \end{frame} \begin{frame} \frametitle{TTFB benchmark} \begin{center} \includegraphics[width=.8\linewidth]{../assets/perf/ttfb.png} \end{center} \end{frame} \begin{frame} \frametitle{Throughput benchmark} \begin{center} \includegraphics[width=.7\linewidth]{../assets/perf/io-0.7-0.8-minio.png} \end{center} \end{frame} % ====================== v0.9.0 =============================== \begin{frame} \begin{center} \includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf} \end{center} \end{frame} \begin{frame} \frametitle{October 2023 - Garage v0.9.0} Focus on \underline{streamlining \& usability} \vspace{2em} \begin{itemize} \item Support multiple HDDs per node \vspace{1em} \item S3 compatibility: \vspace{1em} \begin{itemize} \item support basic lifecycle configurations \vspace{.5em} \item allow for multipart upload part retries \end{itemize} \vspace{1em} \item LMDB by default, deprecation of Sled \vspace{1em} \item New layout computation algorithm \end{itemize} \end{frame} \begin{frame} \frametitle{Layout computation} \begin{overprint} \onslide<1> \begin{center} \includegraphics[width=\linewidth, trim=0 0 0 -4cm]{../assets/screenshots/garage_status_0.9_prod_zonehl.png} \end{center} \onslide<2> \begin{center} \includegraphics[width=.7\linewidth]{../assets/map.png} \end{center} \end{overprint} \vspace{1em} Garage stores replicas on different zones when possible \end{frame} \begin{frame} \frametitle{What a "layout" is} \textbf{A layout is a precomputed index table:} \vspace{1em} {\footnotesize \begin{center} \begin{tabular}{|l|l|l|l|} \hline \textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\ \hline \hline Partition 0 & df-ymk (bespin) & Abricot (scorpio) & Courgette (neptune) \\ \hline Partition 1 & Ananas (scorpio) & Courgette (neptune) & df-ykl (bespin) \\ \hline Partition 2 & df-ymf (bespin) & Celeri (neptune) & Abricot (scorpio) \\ \hline \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ & \hspace{1em}$\vdots$ \\ \hline Partition 255 & Concombre (neptune) & df-ykl (bespin) & Abricot (scorpio) \\ \hline \end{tabular} \end{center} } \vspace{2em} \visible<2->{ The index table is built centrally using an optimal algorithm,\\ then propagated to all nodes } \vspace{1em} \visible<3->{ \footnotesize Oulamara, M., \& Auvolat, A. (2023). \emph{An algorithm for geo-distributed and redundant storage in Garage}.\\ arXiv preprint arXiv:2302.13798. } \end{frame} % ====================== v0.10.0 =============================== \begin{frame} \begin{center} \includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf} \end{center} \end{frame} \begin{frame} \frametitle{October 2023 - Garage v0.10.0 beta} Focus on \underline{consistency} \vspace{2em} \begin{itemize} \item Fix consistency issues when reshuffling data \end{itemize} \end{frame} \begin{frame} \frametitle{Working with weak consistency} Not using consensus limits us to the following: \vspace{2em} \begin{itemize} \item<2-> \textbf{Conflict-free replicated data types} (CRDT)\\ \vspace{1em} {\footnotesize Non-transactional key-value stores such as S3 are equivalent to a simple CRDT:\\ a map of \textbf{last-writer-wins registers} (each key is its own CRDT)} \vspace{1.5em} \item<3-> \textbf{Read-after-write consistency}\\ \vspace{1em} {\footnotesize Can be implemented using quorums on read and write operations} \end{itemize} \end{frame} \begin{frame}[t] \frametitle{CRDT read-after-write consistency using quorums} \vspace{1em} {\small \textbf{Property:} If client 1 did an operation $write(x)$ and received an OK response,\\ \hspace{2cm} and client 2 starts an operation $read()$ after client 1 received OK,\\ \hspace{2cm} then client 2 will read a value $x' \sqsupseteq x$. } \vspace{1.5em} \begin{overprint} \onslide<2-9> \begin{figure} \centering \footnotesize \def\svgwidth{.7\textwidth} \only<2>{\import{../assets/lattice/}{lattice1.pdf_tex}}% \only<3>{\import{../assets/lattice/}{lattice2.pdf_tex}}% \only<4>{\import{../assets/lattice/}{lattice3.pdf_tex}}% \only<5>{\import{../assets/lattice/}{lattice4.pdf_tex}}% \only<6>{\import{../assets/lattice/}{lattice5.pdf_tex}}% \only<7>{\import{../assets/lattice/}{lattice6.pdf_tex}}% \only<8>{\import{../assets/lattice/}{lattice7.pdf_tex}}% \only<9>{\import{../assets/lattice/}{lattice8.pdf_tex}}% \end{figure} \onslide<10> \begin{minipage}{.10\textwidth} ~ \end{minipage} \begin{minipage}{.40\textwidth} \footnotesize \textbf{Algorithm $write(x)$:} \begin{enumerate} \item Broadcast $write(x)$ to all nodes \item Wait for $k > n/2$ nodes to reply OK \item Return OK \end{enumerate} \end{minipage} \begin{minipage}{.40\textwidth} \footnotesize \vspace{1em} \textbf{Algorithm $read()$:} \begin{enumerate} \item Broadcast $read()$ to all nodes \item Wait for $k > n/2$ nodes to reply\\ with values $x_1, \dots, x_k$ \item Return $x_1 \sqcup \dots \sqcup x_k$ \end{enumerate} \end{minipage} \end{overprint} \end{frame} \begin{frame} \frametitle{A hard problem: layout changes} \begin{itemize} \item We rely on quorums $k > n/2$ within each partition:\\ $$n=3,~~~~~~~k\ge 2$$ \item<2-> When rebalancing, the set of nodes responsible for a partition can change:\\ \vspace{1em} \begin{minipage}{.04\linewidth}~ \end{minipage} \begin{minipage}{.40\linewidth} {\tiny \begin{tabular}{|l|l|l|l|} \hline \textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\ \hline \hline Partition 0 & \textcolor{Crimson}{df-ymk} & Abricot & \textcolor{Crimson}{Courgette} \\ \hline Partition 1 & Ananas & \textcolor{Crimson}{Courgette} & \textcolor{Crimson}{df-ykl} \\ \hline Partition 2 & \textcolor{Crimson}{df-ymf} & \textcolor{Crimson}{Celeri} & Abricot \\ \hline \hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ \\ \hline \end{tabular} } \end{minipage} \begin{minipage}{.04\linewidth} $\to$ \end{minipage} \begin{minipage}{.40\linewidth} {\tiny \begin{tabular}{|l|l|l|l|} \hline \textbf{Partition} & \textbf{Node 1} & \textbf{Node 2} & \textbf{Node 3} \\ \hline \hline Partition 0 & \textcolor{ForestGreen}{Dahlia} & Abricot & \textcolor{ForestGreen}{Eucalyptus} \\ \hline Partition 1 & Ananas & \textcolor{ForestGreen}{Euphorbe} & \textcolor{ForestGreen}{Doradille} \\ \hline Partition 2 & \textcolor{ForestGreen}{Dahlia} & \textcolor{ForestGreen}{Echinops} & Abricot \\ \hline \hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ & \hspace{1em}$\dots$ \\ \hline \end{tabular} } \end{minipage} \vspace{2em} \item<3-> During the rebalancing, new nodes don't yet have the data,\\ ~~~~~~~~~~~~~~~~~~~and old nodes want to get rid of the data to free up space\\ \vspace{1.2em} $\to$ risk of inconsistency, \textbf{how to coordinate?} \end{itemize} \end{frame} \begin{frame} \frametitle{Handling layout changes without losing consistency} \begin{minipage}{.55\textwidth} \begin{itemize} \item \textbf{Solution:}\\ \vspace{.5em} \begin{itemize} \item keep track of data transfer to new nodes \vspace{.5em} \item use multiple write quorums\\ (new nodes + old nodes\\ while data transfer is in progress) \vspace{.5em} \item switching reads to new nodes\\ only once copy is finished \end{itemize} \vspace{1em} \item \textbf{Implemented} in v0.10 \vspace{1em} \item \textbf{Validated} with Jepsen testing \end{itemize} \end{minipage} \begin{minipage}{.23\textwidth} \includegraphics[width=3cm]{../assets/jepsen-0.9.png}\\ {\footnotesize Garage v0.9.0} \end{minipage} \begin{minipage}{.2\textwidth} \includegraphics[width=3cm]{../assets/jepsen-0.10.png}\\ {\footnotesize Garage v0.10 beta} \end{minipage} \end{frame} % ====================== v0.10.0 =============================== \begin{frame} \begin{center} \includegraphics[width=.8\linewidth]{../assets/timeline-22-24.pdf} \end{center} \end{frame} \begin{frame} \frametitle{Towards v1.0...} Focus on \underline{security \& stability} \vspace{2em} \begin{itemize} \item \textbf{Security audit} in progress by Radically Open Security \vspace{1em} \item Misc. S3 features (SSE-C, ...) and compatibility fixes \vspace{1em} \item Improve UX \vspace{1em} \item Fix bugs \end{itemize} \end{frame} \begin{frame} \frametitle{...and beyond!} \begin{center} \includegraphics[width=.6\linewidth]{../assets/survey_requested_features.png} \end{center} \end{frame} % ======================================== OPERATING % ======================================== OPERATING % ======================================== OPERATING \section{Operating big Garage clusters} \begin{frame} \frametitle{Operating Garage} \begin{center} \only<1-2>{ \includegraphics[width=.9\linewidth]{../assets/screenshots/garage_status_0.10.png} \\\vspace{1em} \visible<2>{\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_status_unhealthy_0.10.png}} } \end{center} \end{frame} \begin{frame} \frametitle{Garage's architecture} \begin{center} \only<1>{\includegraphics[width=.45\linewidth]{../assets/garage.drawio.pdf}}% \only<2>{\includegraphics[width=.6\linewidth]{../assets/garage_sync.drawio.pdf}}% \end{center} \end{frame} \begin{frame} \frametitle{Digging deeper} \begin{center} \only<1>{\includegraphics[width=.9\linewidth]{../assets/screenshots/garage_stats_0.10.png}} \only<2>{\includegraphics[width=.5\linewidth]{../assets/screenshots/garage_worker_list_0.10.png}} \only<3>{\includegraphics[width=.6\linewidth]{../assets/screenshots/garage_worker_param_0.10.png}} \end{center} \end{frame} \begin{frame} \frametitle{Potential limitations and bottlenecks} \begin{itemize} \item Global: \begin{itemize} \item Max. $\sim$100 nodes per cluster (excluding gateways) \end{itemize} \vspace{1em} \item Metadata: \begin{itemize} \item One big bucket = bottleneck, object list on 3 nodes only \end{itemize} \vspace{1em} \item Block manager: \begin{itemize} \item Lots of small files on disk \item Processing the resync queue can be slow \end{itemize} \end{itemize} \end{frame} \begin{frame} \frametitle{Deployment advice for very large clusters} \begin{itemize} \item Metadata storage: \begin{itemize} \item ZFS mirror (x2) on fast NVMe \item Use LMDB storage engine \end{itemize} \vspace{.5em} \item Data block storage: \begin{itemize} \item Use Garage's native multi-HDD support \item XFS on individual drives \item Increase block size (1MB $\to$ 10MB, requires more RAM and good networking) \item Tune \texttt{resync-tranquility} and \texttt{resync-worker-count} dynamically \end{itemize} \vspace{.5em} \item Other : \begin{itemize} \item Split data over several buckets \item Use less than 100 storage nodes \item Use gateway nodes \end{itemize} \vspace{.5em} \end{itemize} Our deployments: $< 10$ TB. Some people have done more! \end{frame} % ======================================== END % ======================================== END % ======================================== END \begin{frame} \frametitle{Where to find us} \begin{center} \includegraphics[width=.25\linewidth]{../../logo/garage_hires.png}\\ \vspace{-1em} \url{https://garagehq.deuxfleurs.fr/}\\ \url{mailto:garagehq@deuxfleurs.fr}\\ \texttt{\#garage:deuxfleurs.fr} on Matrix \vspace{1.5em} \includegraphics[width=.06\linewidth]{../assets/logos/rust_logo.png} \includegraphics[width=.13\linewidth]{../assets/logos/AGPLv3_Logo.png} \end{center} \end{frame} \end{document} %% vim: set ts=4 sw=4 tw=0 noet spelllang=en :