X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/GMRES2stage.git/blobdiff_plain/70ad0cb4dcbf00dcc4bade65051bf0273854d231..9deeb3b22421122e2872c4c432662811ec125909:/paper.tex diff --git a/paper.tex b/paper.tex index 51eab5c..e4421cd 100644 --- a/paper.tex +++ b/paper.tex @@ -374,6 +374,9 @@ %\title{???} + + + % author names and affiliations % use a multiple column layout for up to two different % affiliations @@ -543,6 +546,7 @@ Iterative Krylov methods; sparse linear systems; error minimization; PETSc; %à % no \IEEEPARstart % You must have at least 2 lines in the paragraph with the drop letter % (should never be an issue) +{\bf RAPH : EST ce qu'on parle de Krylov pour dire que les résidus constituent une base de Krylov... J'hésite... Tof t'en penses quoi?} Iterative methods are become more attractive than direct ones to solve very large sparse linear systems. They are more effective in a parallel context and require less memory and arithmetic operations than direct methods. A number of @@ -771,7 +775,24 @@ Larger experiments .... \end{table*} +\begin{table*} +\begin{center} +\begin{tabular}{|r|r|r|r|r|r|r|r|r|} +\hline + + nb. cores & threshold & \multicolumn{2}{c|}{gmres variant} & \multicolumn{2}{c|}{2 stage CGLS} & \multicolumn{2}{c|}{2 stage LSQR} & best gain \\ +\cline{3-8} + & & Time & \# Iter. & Time & \# Iter. & Time & \# Iter. & \\\hline \hline + 8,192 & 6e-5 & 149.54 & 17,280 & 28.68 & 3,810 & 29.05 & 3,990 & 5.21 \\ + 8,192 & 5e-5 & 792.11 & 109,590 & 76.83 & 10,470 & 65.20 & 9,030 & 12.14 \\ + 16,384 & 4e-5 & 718.61 & 86,400 & 98.98 & 10,830 & 131.86 & 14,790 & 7.26 \\ +\hline +\end{tabular} +\caption{Comparison of FGMRES and 2 stage FGMRES algorithms for ex54 of Petsc (both with the MG preconditioner) with 25000 components per core on Curie (restart=30, s=12), time is expressed in seconds.} +\label{tab:04} +\end{center} +\end{table*} %%%********************************************************* %%%********************************************************* @@ -789,6 +810,7 @@ Larger experiments .... future plan : \\ - study other kinds of matrices, problems, inner solvers\\ - adaptative number of outer iterations to minimize\\ +- other methods to minimize the residuals?\\ - implement our solver inside PETSc