From: Arnaud Giersch Date: Mon, 17 Mar 2014 09:11:07 +0000 (+0100) Subject: s/\"{u}/ü/g + typos X-Git-Tag: ispa14_submission~34^2~2 X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/mpi-energy.git/commitdiff_plain/5cbb41e9f46ba582a492088627d2e1533092f205?ds=inline s/\"{u}/ü/g + typos --- diff --git a/paper.tex b/paper.tex index dc963b5..332f1f1 100644 --- a/paper.tex +++ b/paper.tex @@ -94,13 +94,13 @@ this algorithm to seven MPI benchmarks. These MPI programs are the NAS parallel benchmarks (NPB v3.3) developed by NASA~\cite{44}. Our experiments are executed using the simulator SimGrid/SMPI v3.10~\cite{Casanova:2008:SGF:1397760.1398183} over an homogeneous distributed memory architecture. Furthermore, we compare the -proposed algorithm with Rauber and R\"{u}nger methods~\cite{3}. +proposed algorithm with Rauber and Rünger methods~\cite{3}. The comparison's results show that our algorithm gives better energy-time trade off. This paper is organized as follows: Section~\ref{sec.relwork} presents the works from other authors. Section~\ref{sec.ptasks} shows the execution of parallel tasks and sources of idle times. Section~\ref{sec.energy} resumes the -energy model of homogenous platform. Section~\ref{sec.mpip} evaluates the performance of MPI program. +energy model of homogeneous platform. Section~\ref{sec.mpip} evaluates the performance of MPI program. Section~\ref{sec.verif} verifies the performance prediction model. Section~\ref{sec.compet} presents the energy-performance trade offs objective function. Section~\ref{sec.optim} demonstrates the proposed energy-performance algorithm. Section~\ref{sec.expe} presents the results of our experiments. @@ -148,10 +148,10 @@ program can be used to save energy. In~\cite{1}, Lim et al. developed an algorithm that detects the communication sections and changes the frequency during these sections only. This approach changes the frequency many times because an iteration may contain more than one communication section. The domain -of analytical modeling used for choosing the optimal frequency as inRauber and R\"{u}nger~\cite{3}. they +of analytical modeling used for choosing the optimal frequency as in Rauber and Rünger~\cite{3}. they developed an analytical mathematical model to determine the optimal frequency scaling factor for any number of concurrent tasks. They set the slowest task to maximum frequency for maintaining performance. In this paper we compare our algorithm with -Rauber and R\"{u}nger model~\cite{3}, because their model can be used for any number of +Rauber and Rünger model~\cite{3}, because their model can be used for any number of concurrent tasks for homogeneous platforms. The primary contributions of this paper are: \begin{enumerate} \item Selecting the frequency scaling factor for simultaneously optimizing energy and performance, @@ -240,7 +240,7 @@ The scaling factor is equal to 1 when the frequency set is to the maximum freque The energy consumption model for parallel homogeneous platform depends on the scaling factor \emph S. This factor reduces quadratically the dynamic power. Also, this factor increases the static energy linearly because the execution time is increased~\cite{36}. The energy model depending on the frequency scaling factor for homogeneous platform -for any number of concurrent tasks was developed by Rauber and R\"{u}nger~\cite{3}. This model +for any number of concurrent tasks was developed by Rauber and Rünger~\cite{3}. This model considers the two power metrics for measuring the energy of the parallel tasks as in EQ~(\ref{eq:energy}): @@ -266,9 +266,9 @@ the time value $T_i$ depends on the new frequency value as in EQ~(\ref{eq:si}). = \frac{F_\textit{max}}{F_\textit{new}} \cdot \frac{T_1}{T_i} \end{equation} where $F$ is the number of available frequencies. In this paper we depend on -Rauber and R\"{u}nger energy model EQ~(\ref{eq:energy}) for two reasons: (1)-this model is used +Rauber and Rünger energy model EQ~(\ref{eq:energy}) for two reasons: (1)-this model is used for homogeneous platform that we work on in this paper. 2-we compare our -algorithm with Rauber and R\"{u}nger scaling model. Rauber and R\"{u}nger scaling factor that reduce +algorithm with Rauber and Rünger scaling model. Rauber and Rünger scaling factor that reduce energy consumption derived from the EQ~(\ref{eq:energy}). They take the derivation for this equation (to be minimized) and set it to zero to produce the scaling factor as in EQ~(\ref{eq:sopt}). @@ -424,7 +424,7 @@ EQ~(\ref{eq:max}). Our objective function can works with any energy model or static power values stored in a data file. Moreover, this function works in optimal way when the energy function has a convex form with frequency scaling factor as shown in~\cite{15,3,19}. Energy measurement model is not the -objective of this paper and we choose Rauber and R\"{u}nger model as an example with two +objective of this paper and we choose Rauber and Rünger model as an example with two reasons that mentioned before. \section{Optimal Scaling Factor for Performance and Energy} @@ -598,7 +598,7 @@ EPSA to selects smaller scaling factor values (inducing smaller energy savings). \section{Comparing Results} \label{sec.compare} -In this section, we compare our EPSA algorithm results with Rauber and R\"{u}nger +In this section, we compare our EPSA algorithm results with Rauber and Rünger methods~\cite{3}. He had two scenarios, the first is to reduce energy to optimal level without considering the performance as in EQ~(\ref{eq:sopt}). We refer to this scenario as $R_{E}$. The second scenario is similar to the first @@ -606,7 +606,7 @@ except setting the slower task to the maximum frequency (when the scale $S=1$) to keep the performance from degradation as mush as possible. We refer to this scenario as $R_{E-P}$. The comparison is made in tables~(\ref{table:compare Class A},\ref{table:compare Class B},\ref{table:compare Class C}). These -tables show the results of our EPSA and Rauber and R\"{u}nger scenarios for all the NAS +tables show the results of our EPSA and Rauber and Rünger scenarios for all the NAS benchmarks programs for classes A,B and C. \begin{table}[p] \caption{Comparing Results for The NAS Class A} @@ -736,7 +736,7 @@ As shown in these tables our scaling factor is not optimal for energy saving such as Rauber's scaling factor EQ~(\ref{eq:sopt}), but it is optimal for both the energy and the performance simultaneously. Our $EPSA$ optimal scaling factors has better simultaneous optimization for both the energy and the performance -compared to Rauber and R\"{u}nger energy-performance method ($R_{E-P}$). Also, in +compared to Rauber and Rünger energy-performance method ($R_{E-P}$). Also, in ($R_{E-P}$) method when setting the frequency to maximum value for the slower task lead to a small improvement of the performance. Also the results show that this method keep or improve energy saving. Because of the energy @@ -746,7 +746,7 @@ increased. Figure~(\ref{fig:compare}) shows the maximum distance between the energy saving percent and the performance degradation percent. Therefore, this means it is the same resultant of our objective function EQ~(\ref{eq:max}). Our algorithm always -gives positive energy to performance trade offs while Rauber and R\"{u}nger method +gives positive energy to performance trade offs while Rauber and Rünger method ($R_{E-P}$) gives in some time negative trade offs such as in BT and EP. The positive trade offs with highest values lead to maximum energy savings concatenating with less performance degradation and this the objective of this @@ -758,7 +758,7 @@ than the first. \includegraphics[width=.33\textwidth]{compare_class_A.pdf} \includegraphics[width=.33\textwidth]{compare_class_B.pdf} \includegraphics[width=.33\textwidth]{compare_class_c.pdf} - \caption{Comparing Our EPSA with Rauber and R\"{u}nger Methods} + \caption{Comparing Our EPSA with Rauber and Rünger Methods} \label{fig:compare} \end{figure} @@ -790,5 +790,5 @@ Mésocentre de calcul de Franche-Comté. %%% ispell-local-dictionary: "american" %%% End: -% LocalWords: Badri Charr FIXME Tianhe DVFS HPC NAS NPB SMPI Rauber's Rauber -% LocalWords: CMOS EQ $$EPSA$$ Franche Comté Tflop +% LocalWords: Fanfakh Charr FIXME Tianhe DVFS HPC NAS NPB SMPI Rauber's Rauber +% LocalWords: CMOS EQ EPSA Franche Comté Tflop Rünger