From: raphael couturier Date: Thu, 9 Oct 2014 16:04:33 +0000 (+0200) Subject: update X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/GMRES2stage.git/commitdiff_plain/b599aea7bd0cb52057a014508bf1bccdd41c7770?hp=fdf2e308fad59acb0f3401f7f3d59a8131ee35ae update --- diff --git a/paper.tex b/paper.tex index dd80756..112b322 100644 --- a/paper.tex +++ b/paper.tex @@ -829,15 +829,17 @@ to read the codes available in the PETSc sources. Those problem have been chosen because they are scalable with many cores. We have tested other problem but they are not scalable with many cores. +In the following larger experiments are described on two large scale architectures: Curie and Juqeen... {\bf description...}\\ +{\bf Description of preconditioners} \begin{table*} \begin{center} \begin{tabular}{|r|r|r|r|r|r|r|r|r|} \hline - nb. cores & precond & \multicolumn{2}{c|}{GMRES} & \multicolumn{2}{c|}{TSARM CGLS} & \multicolumn{2}{c|}{TSARM LSQR} & best gain \\ + nb. cores & precond & \multicolumn{2}{c|}{FGMRES} & \multicolumn{2}{c|}{TSARM CGLS} & \multicolumn{2}{c|}{TSARM LSQR} & best gain \\ \cline{3-8} & & Time & \# Iter. & Time & \# Iter. & Time & \# Iter. & \\\hline \hline 2,048 & mg & 403.49 & 18,210 & 73.89 & 3,060 & 77.84 & 3,270 & 5.46 \\ @@ -851,11 +853,23 @@ but they are not scalable with many cores. \hline \end{tabular} -\caption{Comparison of FGMRES and 2 stage FGMRES algorithms for ex15 of Petsc with 25000 components per core on Juqueen (threshold 1e-3, restart=30, s=12), time is expressed in seconds.} +\caption{Comparison of FGMRES and TSARM with FGMRES for example ex15 of PETSc with two preconditioner (mg and sor) with 25,000 components per core on Juqueen (threshold 1e-3, restart=30, s=12), time is expressed in seconds.} \label{tab:03} \end{center} \end{table*} +Table~\ref{tab:03} shows the execution times and the number of iterations of +example ex15 of PETSc on the Juqueen architecture. Differents number of cores +are studied rangin from 2,048 upto 16,383. Two preconditioners have been +tested. For those experiments, the number of components (or unknown of the +problems) per processor is fixed to 25,000. This number can seem relatively +small. In fact, for some applications that need a lot of memory, the number of +components per processor requires sometimes to be small. + +In this Table, we can notice that TSARM is always faster than FGMRES. The last +column shows the ratio between FGMRES and the best version of TSARM according to +the minimization procedure: CGLS or LSQR. + \begin{figure} \centering