version 1.5, 2001/06/20 03:08:05 |
version 1.8, 2001/06/21 03:09:46 |
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% $OpenXM: OpenXM/doc/ascm2001p/homogeneous-network.tex,v 1.4 2001/06/20 02:50:16 noro Exp $ |
% $OpenXM: OpenXM/doc/ascm2001p/homogeneous-network.tex,v 1.7 2001/06/20 05:42:47 takayama Exp $ |
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\subsection{Distributed computation with homogeneous servers} |
\subsection{Distributed computation with homogeneous servers} |
\label{section:homog} |
\label{section:homog} |
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One of the aims of OpenXM is a parallel speedup by a distributed computation |
One of the aims of OpenXM is a parallel speedup by a distributed computation |
with homogeneous servers. |
with homogeneous servers. Let us see some examples. |
%As the current specification of OpenXM does |
%As the current specification of OpenXM does |
%not include communication between servers, one cannot expect |
%not include communication between servers, one cannot expect |
%the maximal parallel speedup. However it is possible to execute |
%the maximal parallel speedup. However it is possible to execute |
Line 12 with homogeneous servers. |
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Line 12 with homogeneous servers. |
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\subsubsection{Competitive distributed computation by various strategies} |
\subsubsection{Competitive distributed computation by various strategies} |
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SINGULAR \cite{Singular} implements {\it MP} interface for distributed |
SINGULAR \cite{Singular} implements MP interface for distributed |
computation and a competitive Gr\"obner basis computation is |
computation and a competitive Gr\"obner basis computation is |
illustrated as an example of distributed computation. |
illustrated as an example of distributed computation by the interface. |
Such a distributed computation is also possible on OpenXM as follows: |
Such a distributed computation is also possible on OpenXM. |
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The client creates two servers and it requests |
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Gr\"obner basis comutations by the Buchberger algorithm the $F_4$ algorithm |
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to the servers for the same input. |
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The client watches the streams by {\tt ox\_select()} |
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and the result which is returned first is taken. Then the remaining |
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server is reset. |
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\begin{verbatim} |
\begin{verbatim} |
extern Proc1,Proc2$ |
extern Proc1,Proc2$ |
Proc1 = -1$ Proc2 = -1$ |
Proc1 = -1$ Proc2 = -1$ |
Line 50 def dgr(G,V,Mod,O) |
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Line 43 def dgr(G,V,Mod,O) |
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return [Win,R]; |
return [Win,R]; |
} |
} |
\end{verbatim} |
\end{verbatim} |
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In the above Asir program, the client creates two servers and it requests |
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Gr\"obner basis computations by the Buchberger algorithm |
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and the $F_4$ algorithm to the servers for the same input. |
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The client watches the streams by {\tt ox\_select()} |
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and the result which is returned first is taken. Then the remaining |
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server is reset. |
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\subsubsection{Nesting of client-server communication} |
\subsubsection{Nesting of client-server communication} |
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Under OpenXM-RFC 100 an OpenXM server can be a client of other servers. |
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Figure \ref{tree} illustrates a tree-like structure of an OpenXM |
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client-server communication. |
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\begin{figure} |
\begin{figure} |
\label{tree} |
\label{tree} |
\begin{center} |
\begin{center} |
Line 78 client-server communication. |
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Line 74 client-server communication. |
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\caption{Tree-like structure of client-server communication} |
\caption{Tree-like structure of client-server communication} |
\end{center} |
\end{center} |
\end{figure} |
\end{figure} |
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%%Prog: load ("dfff"); df_demo(); enter 100. |
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Under OpenXM-RFC 100 an OpenXM server can be a client of other servers. |
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%Figure \ref{tree} |
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Figure 2 |
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illustrates a tree-like structure of an OpenXM |
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client-server communication. |
Such a computational model is useful for parallel implementation of |
Such a computational model is useful for parallel implementation of |
algorithms whose task can be divided into subtasks recursively. |
algorithms whose task can be divided into subtasks recursively. |
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Line 134 algorithms whose task can be divided into subtasks rec |
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Line 136 algorithms whose task can be divided into subtasks rec |
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%\end{verbatim} |
%\end{verbatim} |
% |
% |
A typical example is a parallelization of the Cantor-Zassenhaus |
A typical example is a parallelization of the Cantor-Zassenhaus |
algorithm for polynomial factorization over finite fields. |
algorithm for polynomial factorization over finite fields, |
which is a recursive algorithm. |
which is a recursive algorithm. |
At each level of the recursion, a given polynomial can be |
At each level of the recursion, a given polynomial can be |
divided into two non-trivial factors with some probability by using |
divided into two non-trivial factors with some probability by using |
a randomly generated polynomial as a {\it separator}. |
a randomly generated polynomial as a {\it separator}. |
We can apply the following simple parallelization: |
We can apply the following simple parallelization: |
When two non-trivial factors are generated on a server, |
when two non-trivial factors are generated on a server, |
one is sent to another server and the other factor is factorized on the server |
one is sent to another server and the other factor is factorized on the server |
itself. |
itself. |
%\begin{verbatim} |
%\begin{verbatim} |
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% if ( N == E ) return [F]; |
% if ( N == E ) return [F]; |
% M = field_order_ff(); K = idiv(N,E); L = [F]; |
% M = field_order_ff(); K = idiv(N,E); L = [F]; |
% while ( 1 ) { |
% while ( 1 ) { |
% /* gererate a random polynomial */ |
% /* generate a random polynomial */ |
% W = monic_randpoly_ff(2*E,V); |
% W = monic_randpoly_ff(2*E,V); |
% /* compute a power of the random polynomial */ |
% /* compute a power of the random polynomial */ |
% T = generic_pwrmod_ff(W,F,idiv(M^E-1,2)); |
% T = generic_pwrmod_ff(W,F,idiv(M^E-1,2)); |
Line 251 work well on OpenXM. |
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Line 253 work well on OpenXM. |
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%Such a distributed computation is also possible on OpenXM as follows: |
%Such a distributed computation is also possible on OpenXM as follows: |
% |
% |
%The client creates two servers and it requests |
%The client creates two servers and it requests |
%Gr\"obner basis comutations from the homogenized input and the input itself |
%Gr\"obner basis computations from the homogenized input and the input itself |
%to the servers. |
%to the servers. |
%The client watches the streams by {\tt ox\_select()} |
%The client watches the streams by {\tt ox\_select()} |
%and the result which is returned first is taken. Then the remaining |
%and the result which is returned first is taken. Then the remaining |