Commit 1c3fe532 authored by Michael Davis's avatar Michael Davis
Browse files

[CHEP] Cut/paste presentation into LaTeX doc

parent 56108232
*.aux
*.blg
*.glg
*.glo
*.gls
......
\documentclass[a4paper]{jpconf}
\usepackage{graphicx}
\usepackage{tabularx}
% Set serif font to Paratype
\usepackage{paratype}
\usepackage[T1]{fontenc}
% Colours
\RequirePackage{xcolor} % Colours
\RequirePackage{colortbl} % Colour tables
\usepackage{xcolor} % Colours
\usepackage{colortbl} % Colour tables
% CERN blue is Pantone 286 = RGB 56 97 170, defined as cern@blue below
\definecolor{cern@ltblue}{rgb}{0.415686,0.611765,0.964706} % RGB 106 156 246
......@@ -51,6 +54,187 @@ will interface with EOS and CTA.
Last CHEP paper~\cite{chep2016}
\section{Use Cases}
\subsection{Changing Use Cases for Archival Storage}
\subsubsection{Scaling up for Run 3 and HL--LHC}
\begin{figure}[t]
\centering\includegraphics[width=0.9\textwidth]{images/Storage}
%{\centering\includegraphics[width=0.75\textwidth]{images/Storage}\\[1.7ex]}
%\leftskip1em\rightskip\leftskip\scriptsize\color{black}Source:
%\href{http://iopscience.iop.org/article/10.1088/1742-6596/664/4/042006/meta}{\color{cern@ltblue}Experiences
%and challenges running CERN's high capacity tape archive}\\
%\leftskip5.1em Germ\'{a}n Cancio \textit{et al}, IOP 2015
\end{figure}
\subsubsection{Data for online analysis stored on tape (``Data Carousel'')}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/DataCarousel.png}
\includegraphics[width=\textwidth]{images/DataCarouselChart.png}\\[2ex]
\leftskip1em\rightskip\leftskip\scriptsize\color{black}Source:
\href{https://indico.cern.ch/event/732181/contributions/3019046/}{\color{cern@ltblue}Tape Usage},
Xin Zhao (Brookhaven National Laboratory), ADC Technical Coordination\\
\leftskip5.1em Board Meeting, 28 May 2018
\end{figure}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/TapeCarousel.png}\\[2ex]
\centering\scriptsize\color{black}Source:
\href{https://www.youtube.com/watch?v=RJo13FP4UpI}{\color{cern@ltblue}Fascinating Vintage 20 Cassette Carousel from 1972 : Panasonic RS--296US}
\end{figure}
\section{CASTOR to CTA}
\subsection{CASTOR Architecture}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/CASTOR_Arch}
\end{figure}
\subsection{CERN Tape Archive Architecture}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/CTA_Arch1}
\includegraphics[width=\textwidth]{images/CTA_Arch2A}
\includegraphics[width=\textwidth]{images/CTA_Arch3}
\includegraphics[width=\textwidth]{images/CTA_Arch3A}
\end{figure}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/ObjectStore}
\end{figure}
\begin{figure}[t]
\begin{itemize}
\item Object Store is used for transient requests, queues, statuses and agents\\[2ex]
\item No direct Inter-Process Communication\\[2ex]
\item Resilience against crashes
{\small
\begin{itemize}
\item Guaranteed coherency
\item Agent heartbeat, garbage collection\\[2ex]
\end{itemize}
}
\item Distributed architecture
{\small
\begin{itemize}
\item Allows multiple redundant RADOS instances/CTA Frontends
\item Scale-out scalability\\[2ex]
\end{itemize}
}
\item No single point of failure
\end{itemize}
\end{figure}
\subsection{CTA Architecture}
\vspace{2ex}
{\textcolor{cern@dkblue}{\Large CTA offers the ``Best of Both Worlds''}}\\[1ex]
\begin{itemize}
\item User interface, file access and disk pool management ~ from EOS
\item Tape system management from CASTOR
\item New scalable, robust queuing system to link the two\\[4ex]
\end{itemize}
{\textcolor{cern@dkblue}{\Large CTA design principles}}\\[1ex]
\begin{itemize}
\item Simplicity
\item Scalability
\item Performance\\[4ex]
\end{itemize}
%{\leftskip1em\rightskip\leftskip\scriptsize\color{black}For more details see:
{\scriptsize Full details:
\href{http://iopscience.iop.org/article/10.1088/1742-6596/898/6/062013/pdf}{\color{cern@ltblue}An
efficient, modular and simple tape archiving solution for LHC Run 3},\\
\vspace{-0.8ex}\hspace{5.1em} Steven Murray \textit{et al.} (CERN), CHEP 2016}
%\leftskip5.1em Board Meeting, 28 May 2018
\subsection{CTA Architecture}
\begin{figure}[t]
\renewcommand{\arraystretch}{1.5}
\begin{tabularx}{\textwidth}{>{\raggedright}X>{\raggedright\arraybackslash}X}
\multicolumn{1}{c}{CASTOR} &
\multicolumn{1}{c}{CTA}\\
\hline
Scheduling decisions made at time of user request. &
Scheduling decisions made at time of tape mount.\\
Tape drive may not be available when job reaches the front of the queue. &
Tape drive allocated when job reaches the front of the queue. Reduced latency for users.\\
\end{tabularx}
\begin{tabularx}{\textwidth}{>{\raggedright}X>{\raggedright\arraybackslash}X}
\multicolumn{1}{c}{CASTOR} &
\multicolumn{1}{c}{CTA}\\
\hline
Scheduling decisions made at time of user request. &
Scheduling decisions made at time of tape mount.\\
Tape drive may not be available when job reaches the front of the queue. &
Tape drive allocated when job reaches the front of the queue. Reduced latency for users.\\
\hline
High-priority jobs cannot ~ interrupt running jobs. &
High-priority jobs can preempt lower-priority jobs.\\
& Can switch from repack to data taking and back without operator intervention. System operates at full capacity at all times.\\
\end{tabularx}
\end{figure}
\section{Testing and Deployment}
\subsection{CASTOR Deployment Model}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/CASTOR_Deploy}
\end{figure}
\subsection{CTA Deployment Model}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/CTA_Deploy}
\end{figure}
\subsection{System Testing}
% The scale and stress tests show that the system can operate under a load much heavier than what
% we currently see in operation.
% 100 Hz graph : CASTOR typically operates at not more than 10 Hz.
% Queuing : fill/drain ; first mount after 2 hours ; fill rate slows after 8 hours ? ; final steep gradient is final drain after writing stops
\begin{figure}[t]
\centering
Scale tests and stress tests :\\
10 million files archived in $\approx$27 hours\\[4ex]
\includegraphics[width=\textwidth]{images/SystemTest}
\end{figure}
\subsection{Field Testing}
\begin{figure}[t]
\begin{itemize}
\item Goal of user testing is to ensure that all use cases are covered
\item Rucio/File Transfer Service (FTS) tests with ATLAS have started
\end{itemize}
\includegraphics[width=\textwidth]{images/ATLAS_Test_placeholder}
\vspace{2ex}
{\large Next :}
\begin{itemize}
\item Agree schedule for field testing with all CERN experiments
\end{itemize}
\end{figure}
\subsection{Migration Schedule}
\begin{figure}[t]
\includegraphics[width=\textwidth]{images/Migration}
\end{figure}
\section{Summary}
\subsection{CERN Tape Archive : Summary}
{\textcolor{cern@dkblue}{\Large Use cases for tape archival are changing}}\\[1ex]
\begin{itemize}
\item Increased rate of data taking for Run 3 and HL-LHC
\item Data for online analysis accessed via ``Data Carousel''\\[2ex]
\end{itemize}
{\textcolor{cern@dkblue}{\Large CTA is the ``Best of Both Worlds'' ---\\[1ex]
\hspace{7em}EOS disk and CASTOR tape}}\\[1ex]
\begin{itemize}
\item Simplicity
\item Scalability
\item Performance\\[2ex]
\end{itemize}
{\textcolor{cern@dkblue}{\Large Deployment}}\\[1ex]
\begin{itemize}
\item Now: Field test instances with redundant copies of data
\item LS2: Migration from CASTOR to CTA
\end{itemize}
\section{Conclusions}
\label{conclusions}
......@@ -60,6 +244,5 @@ Last CHEP paper~\cite{chep2016}
\section*{References}
\bibliographystyle{iopart-num}
\bibliography{CHEP2018_CTA}
\end{document}
\end{document}
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment