From: jean-claude Date: Mon, 30 May 2016 09:46:58 +0000 (+0200) Subject: corrections X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/mpi-energy2.git/commitdiff_plain/f48b065ad7039e174cf0042b534ac697c719decb?hp=--cc corrections --- f48b065ad7039e174cf0042b534ac697c719decb diff --git a/mpi-energy2-extension/Heter_paper.tex b/mpi-energy2-extension/Heter_paper.tex index 0973f10..4b55dd4 100644 --- a/mpi-energy2-extension/Heter_paper.tex +++ b/mpi-energy2-extension/Heter_paper.tex @@ -208,14 +208,24 @@ reductions. All the experimental results were conducted over the SimGrid simulator \cite{SimGrid}, which offers easy tools to describe homogeneous and heterogeneous platforms, and to simulate the execution of message passing parallel applications over them. -In this paper, a new frequency selecting algorithm, adapted to grid platforms -composed of heterogeneous clusters, is presented. It is applied to the NAS + +This paper presents the following contributions : +\begin{enumerate} +\item two new energy and performance models for message passing + synchronous applications with iterations running over a heterogeneous grid platform. Both models + take into account communications and slack times. The models can predict the + required energy and the execution time of the application. + +\item a new online frequency selecting algorithm for heterogeneous grid + platforms. The algorithm has a very small overhead and does not need any + training nor profiling. It uses a new optimization function which + simultaneously maximizes the performance and minimizes the energy consumption + of a message passing synchronous application with iterations. The algorithm was applied to the NAS parallel benchmarks and evaluated over a real testbed, the Grid'5000 platform -\cite{grid5000}. It selects for a grid platform running a message passing - application with iterations the vector of frequencies that simultaneously tries to -offer the maximum energy reduction and minimum performance degradation -ratios. The algorithm has a very small overhead, works online and does not need -any training or profiling. +\cite{grid5000}. + +\end{enumerate} + This paper is organized as follows: Section~\ref{sec.relwork} presents some @@ -300,21 +310,7 @@ some heuristic. Chen et al.~\cite{Chen_DVFS.under.quality.of.service.requirements} used a greedy dynamic programming approach to minimize the power consumption of heterogeneous servers while respecting given time constraints. This approach had considerable -overhead. In contrast to the above described papers, this paper presents the -following contributions : -\begin{enumerate} -\item two new energy and performance models for message passing - synchronous applications with iterations running over a heterogeneous grid platform. Both models - take into account communication and slack times. The models can predict the - required energy and the execution time of the application. - -\item a new online frequency selecting algorithm for heterogeneous grid - platforms. The algorithm has a very small overhead and does not need any - training nor profiling. It uses a new optimization function which - simultaneously maximizes the performance and minimizes the energy consumption - of a message passing synchronous application with iterations. - -\end{enumerate} +overhead. @@ -388,7 +384,7 @@ vector of scaling factors can be predicted using Equation (\ref{eq:perf}). \begin{equation} \label{eq:perf} \Tnew = \mathop{\max_{i=1,\dots N}}_{j=1,\dots,M_i}({\TcpOld[ij]} \cdot S_{ij}) - +\mathop{\min_{j=1,\dots,M_i}} (\Tcm[hj]) + +\mathop{\min_{j=1,\dots,M_h}} (\Tcm[hj]) \end{equation} % where $N$ is the number of clusters in the grid, $M_i$ is the number of nodes in @@ -573,7 +569,7 @@ where $Tnew$ is computed as in (\ref{eq:perf}) and $Told$ is computed as in (\re \begin{equation} \label{eq:told} \Told = \mathop{\max_{i=1,\dots N}}_{j=1,\dots,M_i}({\TcpOld[ij]} ) - +\mathop{\min_{j=1,\dots,M_i}} (\Tcm[hj]) + +\mathop{\min_{j=1,\dots,M_h}} (\Tcm[hj]) \end{equation} } In the same way, the energy is normalized by computing the ratio between the diff --git a/mpi-energy2-extension/review/review.pdf b/mpi-energy2-extension/review/review.pdf index 4031421..7aa46bd 100644 Binary files a/mpi-energy2-extension/review/review.pdf and b/mpi-energy2-extension/review/review.pdf differ diff --git a/mpi-energy2-extension/review/review.tex b/mpi-energy2-extension/review/review.tex index d49b795..a7253f6 100644 --- a/mpi-energy2-extension/review/review.tex +++ b/mpi-energy2-extension/review/review.tex @@ -187,7 +187,9 @@ For the variability issue, please refer to the answer to question 1. \section{Questions and remarks of the second reviewer} \begin{enumerate} -\item Move the contributions from related work to introduction +\item Move the contributions from related work to introduction. + +\textbf{Answer:} The contributions were moved to the introduction section. \item Why emphasize it is a grid platform? the presentation of related work follows the logic of heterogeneous CPUs. Grid is only a type of platform with heterogeneous CPUs. @@ -273,13 +275,16 @@ by the scheduler of the operating system of the node. \item Why $T_{old}$ is computed using eq. 12, which applies MAX over computation time and communication time, while in $T_{new}$, max and min operations are applied over computation and communication separately? -\textcolor{blue}{Answer: We agree with the reviewer, $T_{old}$ is the maximum execution time of the application before scaling the frequency and it is computed as in $T_{new}$ equation without scaling factors. So, we have changed the $T_{old}$ in the paper as as follows: +\textbf{Answer:} Both forms can be used for computing $T_{old}$ and $T_{new}$. To avoid this confusion, the same form was used for both equations in the paper. + \begin{equation} \label{eq:told} T_{old} = \mathop{\max_{i=1,2,\dots,N}}_{j=1,2,\dots,M_i} (\Tcp[ij]) + - \mathop{\min_{i=1,2,\dots,N}} (\Tcm[hj] ) + \mathop{\min_{j=1,2,\dots,M_h}} (\Tcm[hj] ) \end{equation} -} +where $h$ is the index of the slowest cluster. + + \item Line 55 on page 16 is to define the slack time, which should be introduced at the beginning of the paper, such as in figure 1.