X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/loba-papers.git/blobdiff_plain/16e862f93239637fe4feae9949de297be4d988a4..380e5cf3507605371bba52eb9a64a9e9c6bcdf24:/loba-besteffort/loba-besteffort.tex diff --git a/loba-besteffort/loba-besteffort.tex b/loba-besteffort/loba-besteffort.tex index 2d0f414..e966c40 100644 --- a/loba-besteffort/loba-besteffort.tex +++ b/loba-besteffort/loba-besteffort.tex @@ -653,7 +653,7 @@ With these constraints in mind, we defined the following metrics: \label{sec.results} In this section, the results for the different simulations will be presented, -and we'll try to explain our observations. +and we will try to explain our observations. \subsubsection{Cluster vs grid platforms} @@ -727,20 +727,33 @@ allocated time, or because we simply decided not to run it. \subsubsection{The \besteffort{} strategy with the load initially on only one node} -Before looking at the different variations, we'll first show that the plain -\besteffort{} strategy is valuable, and may be as good as the \makhoul{} -strategy. On the graphs from the figure~\ref{fig.results1}, these strategies -are respectively labeled ``b'' and ``a''. +Before looking at the different variations, we will first show that the plain +\besteffort{} strategy is valuable, and may be as good as the \makhoul{} +strategy. On the graphs from the figure~\ref{fig.results1}, these strategies +(with virtual load feature) are respectively labeled ``b'' and ``a''. -twice faster on lines -almost equivalent on torus -worse on hcubes +We can see that the relative performance of these strategies is mainly +influenced by the application topology. It is for the line topology that the +difference is the more important. In this case, the \besteffort{} strategy is +nearly twice as fast as the \makhoul{} strategy. This can be explained by the +fact that the \besteffort{} strategy tries to distribute the load faitly between +all the nodes and with the line topology, it is easy to load balance the load +fairly. --> interconnection +On the contrary, for the hypercube topology, the \besteffort{} strategy performs +worse than the \makhoul{} strategy. In this case, the \makhoul{} strategy which +tries to give more load to few neighbors reaches the equilibrum faster. + +For the torus topology, for which the number of links is between the line and +the hypercube, the \makhoul{} strategy is slightly better but the difference is +more nuanced. + +Globally the number of interconnection is very important. The more +interconnection links there are, the faster the \makhoul{} strategy is because +it distributes quickly significant amount of load even if this is unfair between +all the neighbors. In opposition, the \besteffort{} strategy distributes the +load fairly so this strategy is better for low connected strategy. -plus c'est connecté, moins bon est BE car à vouloir trop bien équilibrer -localement, le processeurs se perturbent mutuellement. Du coup, makhoul qui -équilibre moins bien localement est moins perturbé par ces interférences. \subsubsection{With the virtual load extension with the load initially on only one node} @@ -763,6 +776,7 @@ Soit c'est équivalent, soit on gagne -> surtout quand les comms coutent cher et qu'il y a beaucoup de voisins. \subsubsection{The $k$ parameter} +\label{results-k} Dans le cas où les comms coutent cher et ou BE se fait avoir, on peut ameliorer les perfs avec le param k. @@ -845,4 +859,6 @@ Mésocentre de calcul de Franche-Comté. % LocalWords: SimGrid DASUD Comté asynchronism ji ik isend irecv Cortés et al % LocalWords: chan ctrl fifo Makhoul GFlop xml pre FEMTO Makhoul's fca bdee % LocalWords: cdde Contassot Vivier underlaid du de Maréchal Juin cedex calcul -% LocalWords: biblio +% LocalWords: biblio Institut UMR Université UFC Centre Scientifique CNRS des +% LocalWords: École Nationale Supérieure Mécanique Microtechniques ENSMM UTBM +% LocalWords: Technologie Bahi