X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/hpcc2014.git/blobdiff_plain/923e1fe5e990dcc4a47997cc9cfe37cffda3159a..b86834b74008a9af4f14ba12eb228cf6b3d5ec8c:/hpcc.tex?ds=inline diff --git a/hpcc.tex b/hpcc.tex index 02940f0..ab6e020 100644 --- a/hpcc.tex +++ b/hpcc.tex @@ -4,7 +4,7 @@ \usepackage[utf8]{inputenc} \usepackage{amsfonts,amssymb} \usepackage{amsmath} -\usepackage{algorithm} +%\usepackage{algorithm} \usepackage{algpseudocode} %\usepackage{amsthm} \usepackage{graphicx} @@ -173,8 +173,33 @@ our future work after the results. \section{SimGrid} -\AG{Décrire SimGrid~\cite{casanova+legrand+quinson.2008.simgrid} (Arnaud)} - +SimGrid~\cite{casanova+legrand+quinson.2008.simgrid,SimGrid} is a simulation +framework to sudy the behavior of large-scale distributed systems. As its name +says, it emanates from the grid computing community, but is nowadays used to +study grids, clouds, HPC or peer-to-peer systems. +%- open source, developped since 1999, one of the major solution in the field +% +SimGrid provides several programming interfaces: MSG to simulate Concurrent +Sequential Processes, SimDAG to simulate DAGs of (parallel) tasks, and SMPI to +run real applications written in MPI~\cite{MPI}. Apart from the native C +interface, SimGrid provides bindings for the C++, Java, Lua and Ruby programming +languages. The SMPI interface supports applications written in C or Fortran, +with little or no modifications. +%- implements most of MPI-2 \cite{ref} standard [CHECK] + +%%% explain simulation +%- simulated processes folded in one real process +%- simulates interactions on the network, fluid model +%- able to skip long-lasting computations +%- traces + visu? + +%%% platforms +%- describe resources and their interconnection, with their properties +%- XML files + +%%% validation + refs + +\AG{Décrire SimGrid~\cite{casanova+legrand+quinson.2008.simgrid,SimGrid} (Arnaud)} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Simulation of the multisplitting method} @@ -212,8 +237,9 @@ Y_l = B_l - \displaystyle\sum_{\substack{m=1\\ m\neq l}}^{L}A_{lm}X_m \end{equation} is solved independently by a cluster and communications are required to update the right-hand side sub-vector $Y_l$, such that the sub-vectors $X_m$ represent the data dependencies between the clusters. As each sub-system (\ref{eq:4.1}) is solved in parallel by a cluster of processors, our multisplitting method uses an iterative method as an inner solver which is easier to parallelize and more scalable than a direct method. In this work, we use the parallel algorithm of GMRES method~\cite{ref1} which is one of the most used iterative method by many researchers. -\begin{algorithm} -\caption{A multisplitting solver with GMRES method} +\begin{figure} + %%% IEEE instructions forbid to use an algorithm environment here, use figure + %%% instead \begin{algorithmic}[1] \Input $A_l$ (sparse sub-matrix), $B_l$ (right-hand side sub-vector) \Output $X_l$ (solution sub-vector)\vspace{0.2cm} @@ -234,10 +260,23 @@ is solved independently by a cluster and communications are required to update t \State \Return $X_l^k$ \EndFunction \end{algorithmic} +\caption{A multisplitting solver with GMRES method} \label{algo:01} -\end{algorithm} +\end{figure} -Algorithm~\ref{algo:01} shows the main key points of the multisplitting method to solve a large sparse linear system. This algorithm is based on an outer-inner iteration method where the parallel synchronous GMRES method is used to solve the inner iteration. It is executed in parallel by each cluster of processors. For all $l,m\in\{1,\ldots,L\}$, the matrices and vectors with the subscript $l$ represent the local data for cluster $l$, while $\{A_{lm}\}_{m\neq l}$ are off-diagonal matrices of sparse matrix $A$ and $\{X_m\}_{m\neq l}$ contain vector elements of solution $x$ shared with neighboring clusters. At every outer iteration $k$, asynchronous communications are performed between processors of the local cluster and those of distant clusters (lines $6$ and $7$ in Algorithm~\ref{algo:01}). The shared vector elements of the solution $x$ are exchanged by message passing using MPI non-blocking communication routines. +Algorithm on Figure~\ref{algo:01} shows the main key points of the +multisplitting method to solve a large sparse linear system. This algorithm is +based on an outer-inner iteration method where the parallel synchronous GMRES +method is used to solve the inner iteration. It is executed in parallel by each +cluster of processors. For all $l,m\in\{1,\ldots,L\}$, the matrices and vectors +with the subscript $l$ represent the local data for cluster $l$, while +$\{A_{lm}\}_{m\neq l}$ are off-diagonal matrices of sparse matrix $A$ and +$\{X_m\}_{m\neq l}$ contain vector elements of solution $x$ shared with +neighboring clusters. At every outer iteration $k$, asynchronous communications +are performed between processors of the local cluster and those of distant +clusters (lines $6$ and $7$ in Figure~\ref{algo:01}). The shared vector +elements of the solution $x$ are exchanged by message passing using MPI +non-blocking communication routines. \begin{figure} \centering @@ -425,7 +464,7 @@ The authors would like to thank\dots{} % adjust value as needed - may need to be readjusted if % the document is modified later \bibliographystyle{IEEEtran} -\bibliography{hpccBib} +\bibliography{IEEEabrv,hpccBib} \end{document}