% $OpenXM: OpenXM/doc/calc2000p/efficient.tex,v 1.2 2000/07/22 08:11:09 noro Exp $ \documentclass{slides} \usepackage{color} \usepackage{rgb} \usepackage{graphicx} \usepackage{epsfig} \begin{document} \parskip 3pt \fbox{{\huge \color{blue} We Are Efficient}} {\color {red} Real speedup by parallelism} Each process can communicate with any other process on {\color{green} MPI} $\Rightarrow$ {\color{green} Collective operations} similar to \\ {\color{SeaGreen} MPI\_Bcast} and {\color{SeaGreen} MPI\_Reduce} \vskip 8pt {\color{red} An example} : the product of dense univariate polynomials with 3000bit coefficients \vskip 8pt {\color{green} Algorithm}(Shoup) : FFT+Chinese Remainder \vskip 5pt {\color{green} Parallel computing time} : $O((n\log n)/L+n{\color{red}\log L})$\\ No collective operations : $O((n\log n)/L+n{\color{red}L})$\\ ($L$: number of processes, $n$: degree) \vskip 8pt \epsfxsize=17cm \epsffile{3k.ps} \rightline{ {\color{red} {\tt http://www.openxm.org} }} \end{document}