From: Arnaud Giersch Date: Thu, 10 Apr 2014 09:29:45 +0000 (+0200) Subject: Remove bad formating commands. X-Git-Tag: hpcc2014_submission~144 X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/hpcc2014.git/commitdiff_plain/fadf3e9c2be61f86ddebab4672ca769096168535 Remove bad formating commands. --- diff --git a/hpcc.tex b/hpcc.tex index 573bb48..b4d0be3 100644 --- a/hpcc.tex +++ b/hpcc.tex @@ -414,7 +414,7 @@ Décrire SimGrid (Arnaud) Décrire le problème (algo) traité ainsi que le processus d'adaptation à SimGrid. \section{Experimental results} -{\raggedright + When the ``real'' application runs in the simulation environment and produces the expected results, varying the input parameters and the program arguments allows us to compare outputs from the code execution. We have noticed from this @@ -428,9 +428,7 @@ algorithm but also to get the main objective of the experimentation of the simulation in having an execution time in asynchronous less than in synchronous mode, in others words, in having a ``speedup'' less than 1 (Speedup = Execution time in synchronous mode / Execution time in asynchronous mode). -} -{\raggedright A priori, obtaining a speedup less than 1 would be difficult in a local area network configuration where the synchronous mode will take advantage on the rapid exchange of information on such high-speed links. Thus, the methodology adopted @@ -438,36 +436,25 @@ was to launch the application on clustered network. In this last configuration, degrading the inter-cluster network performance will "penalize" the synchronous mode allowing to get a speedup lower than 1. This action simulates the case of clusters linked with long distance network like Internet. -} -{\raggedright As a first step, the algorithm was run on a network consisting of two clusters containing fifty hosts each, totaling one hundred hosts. Various combinations of the above factors have providing the results shown in Table~\ref{tab.cluster.2x50} with a matrix size ranging from Nx = Ny = Nz = 62 to 171 elements or from 62$^{3}$ = 238328 to 171$^{3}$ = 5,211,000 entries. -} -{\raggedright Then we have changed the network configuration using three clusters containing respectively 33, 33 and 34 hosts, or again by on hundred hosts for all the clusters. In the same way as above, a judicious choice of key parameters has permitted to get the results in Table~\ref{tab.cluster.3x33} which shows the speedups less than 1 with a matrix size from 62 to 100 elements. -} -{\raggedright In a final step, results of an execution attempt to scale up the three clustered configuration but increasing by two hundreds hosts has been recorded in Table~\ref{tab.cluster.3x67}. -} -{\raggedright Note that the program was run with the following parameters: -} -%{\raggedright -\textbullet{} \textbf {SMPI parameters:} -%} +\paragraph*{SMPI parameters} \begin{itemize} \item HOSTFILE : Hosts file description. @@ -477,9 +464,7 @@ lat latency , ... ). \end{itemize} -%{\raggedright -\textbullet{} \textbf {Arguments of the program:} -%} +\paragraph*{Arguments of the program} \begin{itemize} \item Description of the cluster architecture; @@ -511,19 +496,14 @@ lat latency , ... ). \includegraphics[width=128pt]{img-2.eps} \end{table} -{\raggedright -\textbf{Interpretations and comments} -} +\paragraph*{Interpretations and comments} -{\raggedright After analyzing the outputs, generally, for the configuration with two or three clusters including one hundred hosts (Tables~\ref{tab.cluster.2x50} and~\ref{tab.cluster.3x33}), some combinations of the used parameters affecting the results have given a speedup less than 1, showing the effectiveness of the asynchronous performance compared to the synchronous mode. -} -{\raggedright In the case of a two clusters configuration, Table~\ref{tab.cluster.2x50} shows that with a deterioration of inter cluster network set with 5 Mbits/s of bandwidth, a latency in order of a hundredth of a millisecond and a system power of one GFlops, an @@ -536,9 +516,7 @@ Maintaining such a system power but this time, increasing network throughput inter cluster up to 50 Mbits /s, the result of efficiency of about 40\% is obtained with high external precision of E-11 for a matrix size from 110 to 150 side elements . -} -{\raggedright For the 3 clusters architecture including a total of 100 hosts, Table~\ref{tab.cluster.3x33} shows that it was difficult to have a combination which gives an efficiency of asynchronous below 80 \%. Indeed, for a matrix size of 62 elements, equality @@ -546,13 +524,10 @@ between the performance of the two modes (synchronous and asynchronous) is achieved with an inter cluster of 10 Mbits/s and a latency of E- 01 ms. To challenge an efficiency by 78\% with a matrix size of 100 points, it was necessary to degrade the inter cluster network bandwidth from 5 to 2 Mbit/s. -} -{\raggedright A last attempt was made for a configuration of three clusters but more power with 200 nodes in total. The convergence with a speedup of 90 \% was obtained with a bandwidth of 1 Mbits/s as shown in Table~\ref{tab.cluster.3x67}. -} \section{Conclusion}